ExSnus Designing a Prototype of a Social Snus Cessation Mobile Ap- plication with an Integrated Artificial Intelligence Function for University Students in Sweden Master’s thesis in Biomedical engineering ALBA PUYUELO CITOLER DEPARTMENT OF ELECTRICAL ENGINEERING CHALMERS UNIVERSITY OF TECHNOLOGY Gothenburg, Sweden 2024 www.chalmers.se www.chalmers.se Master’s thesis 2024 ExSnus Designing a Prototype of a Social Snus Cessation Mobile Application with an Integrated Artificial Intelligence Function for University Students in Sweden ALBA PUYUELO CITOLER Electrical Engineering Signal Processing and Biomedical Engineering Chalmers University of Technology Gothenburg, Sweden 2024 ExSnus Designing a Prototype of a Social Snus Cessation Mobile Application with an Inte- grated Artificial Intelligence Function for University Students in Swedeny ALBA PUYUELO CITOLER © ALBA PUYUELO CITOLER, 2024. Supervisor: Eunji Lee, Signal Processing and Biomedical Engineering, Electrical Engineering Co-supervisor: Jungna Lee Examiner: Andreas Fhager, Signal Processing and Biomedical Engineering, Electri- cal Engineering Master’s Thesis 2024 Department of Electrical Engineering Division of Signal Processing and Biomedical Engineering Chalmers University of Technology SE-412 96 Gothenburg Telephone +46 31 772 1000 Cover: A university student using the prototype of the ExSnus application. Typeset in LATEX, template by Kyriaki Antoniadou-Plytaria Printed by Chalmers Reproservice Gothenburg, Sweden 2024 iv ExSnus Designing a Prototype of a Social Snus Cessation Mobile Application with an Inte- grated Artificial Intelligence Function for University Students in Sweden ALBA PUYUELO CITOLER Department of Electrical Engineering Chalmers University of Technology Abstract The increasing use of snus, particularly among Swedish youth, coupled with growing evidence of its health risks, presents a pressing public health concern. Among the existing approaches that aid individuals in overcoming addictive behaviors, mobile health applications have emerged as a rapidly growing, accessible, and cost-effective alternative to traditional therapy. These applications aim to educate users and pro- vide them with the necessary tools for their cessation journey. However, there has been little research investigating the integration of social aspects and artificial intel- ligence (AI) assistance within such mobile appications to enhance user support for snus use cessation. This project focuses on the design of a mobile application called ExSnus, studying the diverse factors influencing individuals’ behaviors towards snus to then implement several strategies within the application framework to facilitate cessation. Based on a Persuasive Systems Design framework, ExSnus emphasizes the role of social interaction. Additionally, the potential role of AI as an assistant for snus cessation is explored. Key findings from research literature and user interviews revealed that social influence, cultural normalization, and health concerns are signif- icant factors in snus use and cessation. The designed prototype features interactive social support and an AI counselor to address these factors, which were positively received during usability testing. ExSnus effectively integrates principles from a Persuasive Systems Design framework, providing a user-friendly and engaging tool for snus cessation. Keywords: snus cessation, mobile health application, artificial intelligence, social application, persuasive health technology. v Acknowledgements I would first like to thank my supervisor Eunji Lee and my co-supervisor Jungna Lee for their knowledge, time, and advice that have guided me throughout this project. I look forward to continuing our collaboration on the future of this project. I also extend my gratitude to Andreas Fhager, my examiner, for his valuable contribution. Secondly, I would like to thank all the participants of the student interviews because their contributions have been essential for the development of this project. Finally, I am deeply grateful to my family and the friends I have made during these two amazing years here in Gothenburg for their unconditional support. Alba Puyuelo Citoler, Gothenburg, June 2024 vii List of Acronyms Below is the list of acronyms that have been used throughout this thesis listed in alphabetical order: AI Artificial Intelligence ACT Acceptance and Commitment Therapy CBT Cognitive Behavioral Therapy DT Design Thinking DTT Distress Tolerance Training EU European Union NRT Nicotine Replacement Therapy PHT Persuasive Health Technology PSD Persuasive Systems Design PT Persuasive Technology SD Service Design SUS System Usability Scale UI User Interface UML Unified Modeling Language ix Contents List of Acronyms ix List of Figures xv List of Tables xvii 1 Introduction 1 1.1 Aim . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1.2 Research Questions . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1.3 Assumptions and Limitations . . . . . . . . . . . . . . . . . . . . . . 1 2 Background 3 2.1 Snus Consumption Statistics . . . . . . . . . . . . . . . . . . . . . . . 3 2.2 Physiological and Cognitive Effects that Contribute to Snus’ Addic- tion and Motivations to Quit . . . . . . . . . . . . . . . . . . . . . . . 6 2.3 Cessation Consequences . . . . . . . . . . . . . . . . . . . . . . . . . 7 2.4 Snus Cessation Treatments . . . . . . . . . . . . . . . . . . . . . . . . 8 3 Theory 11 3.1 Adopted Design Methodologies . . . . . . . . . . . . . . . . . . . . . 11 3.1.1 Service Design for the Design of mHealth Applications . . . . 11 3.1.2 Persuasive Health Technology . . . . . . . . . . . . . . . . . . 12 3.1.3 User Interface Design . . . . . . . . . . . . . . . . . . . . . . . 13 3.2 Artificial Intelligence Counseling in Health . . . . . . . . . . . . . . . 13 3.3 Ethical Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . 14 4 Methods 17 4.1 Research Approach . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 4.1.1 Preparatory Research . . . . . . . . . . . . . . . . . . . . . . . 18 4.1.2 Interviews with Snus Users . . . . . . . . . . . . . . . . . . . . 19 4.2 Ideation of the Mobile Application . . . . . . . . . . . . . . . . . . . 20 4.3 Prototyping of the Mobile Application . . . . . . . . . . . . . . . . . 21 4.3.1 Sketching . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 4.3.2 Interactive Click Modeling . . . . . . . . . . . . . . . . . . . . 22 4.4 Usability Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 5 Results 25 xi Contents 5.1 mHealth Applications and Cognitive Behavioral Therapy for Snus Cessation and Their Incorporation in the Functionalities of the Ap- plication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 5.2 Interviews Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 5.2.1 Social Influence and Cultural Normalization . . . . . . . . . . 29 5.2.2 Addiction and Use . . . . . . . . . . . . . . . . . . . . . . . . 29 5.2.3 Health Concerns and Motivations for Cessation . . . . . . . . 29 5.2.4 Cessation Support and Technology Skepticism . . . . . . . . . 30 5.3 Persona . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 5.4 Use Cases . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 5.5 App Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44 5.5.1 Sketches . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44 5.5.2 Wireframe and Functionalities of ExSnus Depicted by Screens 44 5.5.2.1 Screens Corresponding to Use Case 1: Create Profile 47 5.5.2.2 Screens Corresponding to Use Case 2: Record Snus Usage and Use Case 3: Record Craving Overcame . . 49 5.5.2.3 Screens Corresponding to Use Case 4: Visualize Dash- board . . . . . . . . . . . . . . . . . . . . . . . . . . 51 5.5.2.4 Screens Corresponding to Use Case 5: Visualize Time- line . . . . . . . . . . . . . . . . . . . . . . . . . . . 51 5.5.2.5 Screens Corresponding to Use Case 6: Engage with Social Features . . . . . . . . . . . . . . . . . . . . . 55 5.5.2.6 Screens Corresponding to Use Case 7: Profile Man- agement . . . . . . . . . . . . . . . . . . . . . . . . . 55 5.5.2.7 Screens Corresponding to Use Case 8: Receive Noti- fications . . . . . . . . . . . . . . . . . . . . . . . . . 58 5.5.2.8 Screens Corresponding to Use Case 9: Chat with AI Counselor . . . . . . . . . . . . . . . . . . . . . . . . 58 5.5.3 Iteractive Digital App Prototype . . . . . . . . . . . . . . . . 59 5.6 Usability Test Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . 59 5.6.1 Results from the Questionnaire and the Interview . . . . . . . 60 5.6.2 SUS questionnaire . . . . . . . . . . . . . . . . . . . . . . . . 61 5.6.3 Design Modifications Based on the the Feedback Obtained of the Usability Testing . . . . . . . . . . . . . . . . . . . . . . . 61 6 Discussion 67 6.1 Research Questions and Answers . . . . . . . . . . . . . . . . . . . . 67 6.1.1 How can a social snus cessation mobile application, with an integrated AI function, be designed to address the main factors that influence potential end users’ behaviors towards snus? . . 67 6.1.1.1 What are the main factors that influence snus use and how can a mobile application be designed to combat them? . . . . . . . . . . . . . . . . . . . . . . 68 6.1.1.2 How can a social snus cessation mobile application be designed to incorporate a persuasive technology framework? . . . . . . . . . . . . . . . . . . . . . . . 69 xii Contents 6.1.1.3 How can a snus cessation mobile application be de- signed to incorporate an integrated AI function? . . 70 6.1.1.4 How such designed app is perceived by potential end users? . . . . . . . . . . . . . . . . . . . . . . . . . . 70 6.2 Health Information Presentation . . . . . . . . . . . . . . . . . . . . . 71 6.3 Future Work . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71 7 Conclusion 73 Bibliography 75 A Appendix I A.1 A 15-point checklist of criteria for good thematic analysis . . . . . . . I A.2 Persuasive Systems Design Framework: Design Principles . . . . . . . II A.3 Design of ExSnus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . III A.3.1 Sketches . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . III A.3.2 Wireframe of ExSnus . . . . . . . . . . . . . . . . . . . . . . . III A.3.3 Interactive Prototype of ExSnus . . . . . . . . . . . . . . . . . III A.4 Usability Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . X A.4.1 Consent and Information Form . . . . . . . . . . . . . . . . . X A.4.2 Initial Questionnaire . . . . . . . . . . . . . . . . . . . . . . . X A.4.3 Tasks to Perform . . . . . . . . . . . . . . . . . . . . . . . . . XI xiii Contents xiv List of Figures 2.1 Comparison of the change in cigarette consumption compared to snus consumption in Sweden [5]. . . . . . . . . . . . . . . . . . . . . . . . 4 2.2 Percentage of students in grade 9 who use snus (daily/almost daily or sporadically) during the period 2012-2023, broken down by gender (as stated in Swedish in the legend, green is the total, purple is female, and orange is male) [11]. . . . . . . . . . . . . . . . . . . . . . . . . . 4 2.3 Percentage of 2nd-year high school students who use snus (daily/al- most daily or sporadically) during the period 2012-2023, broken down by gender (as stated in Swedish in the legend, green is the total, pur- ple is female, and orange is male) [11]. . . . . . . . . . . . . . . . . . 5 2.4 Percentage of 9th-grade and 2nd-year high school students who have used nicotine snus at least once during the period 2021-2023 [11]. . . 5 4.1 Project steps followed in the application design based on the Service Design process [11, 46]. . . . . . . . . . . . . . . . . . . . . . . . . . . 17 5.1 Persona that represents a potential user of the project’s app. The image of the persona was generated using the website This Person Does not Exist1. The layout was created based on a template from Visme2and the icons were from Flaticon3. . . . . . . . . . . . . . . . . 35 5.2 UML use case diagram for ExSnus. It was drawn using the Visual- Paradigm Online tool4. . . . . . . . . . . . . . . . . . . . . . . . . . . 45 5.3 Example of an initial sketch containing some of the application’s main screens and functioning, based on the defined use cases. . . . . . . . . 46 5.4 Wireframe section showing all the screens corresponding to the ap- plication functionalities of the Use Case 1, where the user sets the profile and enters information related to snus consumption and goals for the cessation journey. . . . . . . . . . . . . . . . . . . . . . . . . . 48 5.5 Wireframe section showing the main menu buttons and which screen they give access to, as well as how they look selected and unselected. 49 5.6 Wireframe section showing the screens for recording snus usage and cravings overcome. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50 5.7 Wireframe section showing the dashboard screen’s initial state when no activities have been registered yet. . . . . . . . . . . . . . . . . . . 52 5.8 Wireframe section showing the dashboard screens. . . . . . . . . . . . 53 5.9 Wireframe section showing the timeline screens. . . . . . . . . . . . . 54 5.10 Wireframe section showing the forum screens. . . . . . . . . . . . . . 56 xv List of Figures 5.11 Wireframe section showing the profile screen. . . . . . . . . . . . . . . 57 5.12 Wireframe section showing the AI chatbot screens. . . . . . . . . . . 58 5.13 Example of some main screens from the app final design. From left to right: Dashboard, Timeline, Forum, and AI chatbot. . . . . . . . . 59 5.14 Usability Evaluation of ExSnus Using System Usability Scale (SUS) . 62 A.1 Example of an initial sketch containing some of the application’s main screens and functioning, based on the defined use cases. . . . . . . . . IV A.2 Example of an initial sketch containing some of the application’s main screens and functioning, based on the defined use cases. . . . . . . . . V A.3 Example of an initial sketch containing some of the application’s main screens and functioning, based on the defined use cases. . . . . . . . . VI A.4 Example of an initial sketch containing some of the application’s main screens and functioning, based on the defined use cases. . . . . . . . . VII A.5 Example of an initial sketch containing some of the application’s main screens and functioning, based on the defined use cases. . . . . . . . . VIII A.6 Example of an initial sketch containing some of the application’s main screens and functioning, based on the defined use cases. . . . . . . . . IX xvi List of Tables 2.1 Timeline of withdrawal symptoms after quitting snus [22]. . . . . . . 7 5.1 Comparison of Snus Cessation Mobile Applications. . . . . . . . . . . 25 5.2 Use Case 1: User Creates a Profile . . . . . . . . . . . . . . . . . . . 30 5.3 Use Case 2: User Records Snus Usage . . . . . . . . . . . . . . . . . . 32 5.4 Use Case 3: User Records Craving Overcame . . . . . . . . . . . . . . 33 5.5 Use Case 4: User Visualizes Dashboard . . . . . . . . . . . . . . . . . 36 5.6 Use Case 5: User Visualizes Timeline . . . . . . . . . . . . . . . . . . 37 5.7 Use Case 6: User Engages with Social Features . . . . . . . . . . . . . 39 5.8 Use Case 7: User Manages Their Profile . . . . . . . . . . . . . . . . 40 5.9 Use Case 8: User Receives Notifications . . . . . . . . . . . . . . . . . 42 5.10 Use Case 9: User Chats with AI Counselor . . . . . . . . . . . . . . . 43 5.11 Changes Made in the Design of ExSnus after the Usability Testing . . 62 xvii List of Tables xviii 1 Introduction 1.1 Aim This study aims to explore a possible design for a social mobile application tailored to assist university students in Sweden with snus cessation, incorporating an arti- ficial intelligence (AI) feature. The application design will follow a service design process and adhere to the persuasive technology framework, ensuring the integration of both the social aspect and the AI functionalities. Additionally, user’s education about snus use and quitting consequences will be part of the mobile application’s features. The mobile application will also be designed to be intuitive and user- friendly, presenting health-related information in a clear way. Given the rising snus use among youth, predominant mobile application users, this initiative is timely. By providing instant and free access to a cessation tool, the project aims to make quitting snus more approachable for university students. This approach directly addresses the accessibility and engagement preferences of the younger demographic, making it a potentially effective tool in reducing snus usage. 1.2 Research Questions 1. How can a social snus cessation mobile application, with an integrated AI function, be designed to address the main factors that influence potential end users’ behaviors towards snus? (a) What are the main factors that influence snus use and how can a mobile application be designed to combat them? (b) How can a social snus cessation mobile application be designed to incor- porate a persuasive technology framework? (c) How can a snus cessation mobile application be designed to incorporate an integrated AI function? (d) How is such a designed app perceived by potential end users? 1.3 Assumptions and Limitations The scope of this project is limited to high fidelity prototypes, so modifications in the final design due to technical constraints are not considered. Hence, it is assumed that the obtained mobile application’s design can be further refined during subse- 1 1. Introduction quent development phases. For the same reason, the integration of the AI chatbot is limited to a design recommendation. Additionally, time constraints may limit the complete improvement of the design based on potential end-users’ feedback, which will be considered as future work. Moreover, the mobile application is mainly directed towards young people, and the usability testing is conducted with a small group of university students. This focus can potentially introduce bias and limit feedback diversity that could otherwise be obtained from other user demographics. 2 2 Background This section delves into the statistics of snus use, the physiological and behavioral dimensions of snus consumption, highlighting the factors that render it addictive and challenging to abandon, as well as the current techniques employed to assist in its cessation. This project’s application design addresses these vulnerabilities to provide effective support for users embarking into their snus cessation journey. 2.1 Snus Consumption Statistics Tobacco use is a leading cause of death globally. According to World Health Or- ganization, it is reported that tobacco kills half of its users, corresponding to 8 million deaths annually including non-smokers exposed to second-hand smoke [2]. In Europe, smoking accounts for 16% of adult deaths [3], with half of smokers dying on average 14 years earlier than non-smokers [4]. Unlike other European countries where smoking rates remain a primary concern, Sweden has seen a notable decline in smoking prevalence. This shift is largely attributed to the widespread adoption of snus. Snus is a moist oral tobacco product that is placed behind the upper lip in loose form or portioned pouches where the active constituents, mainly nicotine, are absorbed through the oral mucosa [6]. Its sale is prohibited in all European Union (EU) countries except Sweden, and it is also available in Norway since it is not an EU member and thus not bound by EU legislation [3]. Despite perceptions of snus as a less harmful alternative to cigarettes [3], several studies show its associated health risks, including increased mortality rates and potential links to cardiovascular and cancer-related deaths [6, 7, 8]. Recent statistics indicate that 13.6% of Swedes engage in daily snus consumption [9]. This trend is particularly alarming among younger demographics, with a notable increase in usage rates from 7% to 14% among 15-16- year-old males from 1991 to 2020, and a rise from 1% to 7% among females of the same age group [10]. While lifetime snus use was less common among young girls, recent data reveals an upwards trend in snus usage by them, highlighting a shift in traditional gender patterns of tobacco use. Last year reports from the Swedish Public Health Agency further illuminate this trend [11], showing significant usage among 9th-grade students and 2nd-year high school students, with both groups reporting increased experimentation with nicotine snus products (see Figures 2.2, 2.3, 2.4). 3 2. Background Figure 2.1: Comparison of the change in cigarette consumption compared to snus consumption in Sweden [5]. Figure 2.2: Percentage of students in grade 9 who use snus (daily/almost daily or sporadically) during the period 2012-2023, broken down by gender (as stated in Swedish in the legend, green is the total, purple is female, and orange is male) [11]. 4 2. Background Figure 2.3: Percentage of 2nd-year high school students who use snus (daily/almost daily or sporadically) during the period 2012-2023, broken down by gender (as stated in Swedish in the legend, green is the total, purple is female, and orange is male) [11]. Figure 2.4: Percentage of 9th-grade and 2nd-year high school students who have used nicotine snus at least once during the period 2021-2023 [11]. 5 2. Background The increasing popularity of snus among Swedish youth, despite the mounting ev- idence of its health risks, entails a critical public health issue. As snus use grows, particularly in younger demographics, it becomes imperative to address this trend with targeted interventions. Education on health risks related to snus use within effective cessation approaches is necessary to mitigate its impact on public health and protect future generations. 2.2 Physiological and Cognitive Effects that Con- tribute to Snus’ Addiction and Motivations to Quit Snus exerts several positive effects on the body, primarily attributed to its nicotine content, a highly addictive substance that attracts individuals to its use. Snus in- duces relaxation, aiding concentration, and enhances mood, resulting in a cheerful feeling. The duration of this effect typically lasts around half an hour, depending on the nicotine level [12]. Furthermore, snus consumption can be associated with certain beliefs and cognitive distortions that also contribute to dependency, similar to smoking. These beliefs include the notion that snus use helps relieve stress or the belief that it is necessary to cope with challenging emotions. Cognitive distortions, such as underestimating the health risks of snus and overestimating its benefits, play a role in reinforcing these addictive behaviors [13]. Other influential factors in snus consumption include that it is perceived as a less risky alternative to cigarettes or a help during smoking cessation [14], coupled with its cultural significance in Sweden [15]. These aspects contribute to the perception that snus is relatively harmless. The presented factors show that nicotine addiction depends on several influences, such as the how much the person has been exposed to it, culture, socioeconomic position, and education background; making it a complex physiological process [16]. Several studies have shown that snus use can lead to overall morbidity and mortality [6, 7], which motivates individuals to quit it. A study conducted among young male and female conscripts at the beginning of their military service in Finnish Defense Forces units showed that almost half of daily snus users were willing to quit [16]. Snus use has also increased in Finland as large traveller imports for personal use have contributed to its wide availability in this country [17]. The study also highlighted that the perception of snus-related health risks and getting advice to quit positively impacted their motivation to quit snus. Hence, it is crucial to incorporate both counseling and education about the dangers of snus use into the designed mobile health application directed to help people quit snus. This approach can significantly enhance the motivation of snus users to quit and should be a key consideration in this study. Another study, conducted among Swedish smokers aged 16-84 who used snus as a method to quit smoking, uncovered additional reasons to quit snus [9]. These reasons included health issues such as high blood pressure and dental problems, economic concerns due to the high price of snus, negative impacts on relationships 6 2. Background due to complaints about the smell, and the habit being perceived as disgusting. Interestingly, some cited challenges in carrying snus abroad and purchasing it as a reason to quit. Therefore, the economic aspect can be another incentive considered in this study. 2.3 Cessation Consequences Quitting snus can be a challenging process due to its nicotine content, a highly ad- dictive substance that affects neurotransmitters in the brain’s reward system. The withdrawal symptoms experienced when quitting snus are similar to those encoun- tered when quitting smoking [18]. These withdrawal symptoms commonly include intense cravings and mood changes such as restlessness, irritability, and difficulty focusing and sleeping [19, 20]. It is essential for individuals aiming to quit snus to be aware of these symptoms and their timeline. Understanding that these symptoms are temporary can help them maintain their motivation throughout the cessation journey [21]. Quitting snus involves a series of stages and symptoms, as outlined in Table 2.1. Understanding these stages and symptoms is crucial for individuals undergoing the quitting process. It enables them to anticipate what they might encounter and develop strategies to effectively manage these symptoms, reducing in this way the risk of relapse. Table 2.1: Timeline of withdrawal symptoms after quitting snus [22]. Days after quitting Symptoms 1-3 Physical withdrawal symptoms are intense, including strong cravings for snus, dizziness, nausea, and difficul- ties focusing and sleeping. However, during this time, there is a complete restoration of taste and smell that may have been reduced by snus use. 4-5 Cravings for snus start to reduce, and some individuals may experience a few good days. Others may have re- curring headaches, which can persist during the first 1-2 months but gradually become less frequent. 6-7 As the worst snus cravings subside, individuals may experience sweet cravings, leading to concerns about weight gain after quitting. Headaches and mood issues, such as irritability or melancholy, are also common. Af- ter the first week, sleep typically improves, and nicotine is completely eliminated from the body. 2nd week Blood sugar levels can still be challenging for most, and sweet cravings persist. Sudden and strong irritability may occur. 7 2. Background 4th week Oral health improvements become noticeable, with ex- posed tooth necks and changes in the mucous membrane disappearing. These improvements continue throughout the first year of being snus-free. 5th-6th week Around 40 days after quitting, many individuals expe- rience a crisis period. This happens because habits de- veloped over an extended period have become depen- dencies. Quitting is more complex than mere nicotine abstinence, as the brain needs to unlearn a habit in- tricately linked with a rewarding nicotine kick. At this point, individuals may suffer a decline in motivation and determination to avoid relapse. 7th-8th week After overcoming the 40-day crisis, a lighter period fol- lows, although some former snus users may experience moments of mental fatigue. Engaging in other activities, such as exercise, can help manage this condition. 12th-13th week After 90 days a new milestone is reached where life with- out snus is finally manageable. By this time, the 40- day crisis is usually behind, and a lighter period fol- lows. Some former snus users may experience moments of mental fatigue, which can be managed by engaging in activities like exercise. One year The time required for the body to return to a state as if snus had never been used depend on the duration and intensity of snus consumption. While the restoration of nicotine dependency is a relatively quick process, it takes longer to completely mitigate the increased risk of conditions such as diabetes. 2.4 Snus Cessation Treatments It is crucial to develop effective cessation strategies to address the health risks as- sociated with snus use. Over the years, various treatments have been developed to support smoking cessation efforts, which can also be applied for quitting snus. Nicotine Replacement Therapy (NRT) is the most prevalent method for assisting cessation, utilizing products that administer controlled nicotine doses to alleviate cravings and withdrawal symptoms experienced during quitting [21]. Available in various forms such as patches, gums, lozenges, nasal sprays, and inhalers, NRT can be more effective when using a combination of long-acting and short-acting prod- ucts, such as the patch and the gum respectively, to manage withdrawal symptoms [23]. Additionally, non-nicotine medications like Varenicline serve for the same pur- pose, offering an alternative approach to managing dependency [24]. 8 2. Background These treatments’ effectiveness is enhanced when complemented with guidance or counseling, typically provided by healthcare professionals [23, 25]. This counseling usually involves cognitive approaches that help patients modify their attitudes to- wards tobacco and snus use, with Cognitive Behavioral Therapy (CBT) being one of the most established methods for managing nicotine withdrawal during smoking cessation [26]. CBT focuses on identifying maladaptive thoughts and behaviors to then alter them. It helps individuals recognize their smoking triggers to develop healthier coping mechanisms, such as engaging in healthy activities or using relax- ation techniques to handle cravings [13]. Moreover, CBT emphasizes the value of setting achievable goals and creating a practical quit plan to prevent relapse, along- side other strategies such as self-reminders of the reasons to quit and rewards for resisting cravings [27, 28, 19]. The CBT method is considered when defining this project’s application functionalities. Other cognitive interventions that might aid smokers with smoking cessation, and thus can also be applied for snus cessation, are the mindful-based ones. These tech- niques teach individuals to mindfully manage negative emotions, cravings, and other related nicotine withdrawal symptoms [29]. These include mindfulness training, ac- ceptance and commitment therapy (ACT), distress tolerance training (DTT), and yoga. First, mindfulness training involves breathing techniques and other guided tech- niques such as guided imagery or mindfulness walking [30, 31]. These techniques teach individuals to observe their thoughts and feelings without judgement and let them pass. As nicotine withdrawal symptoms usually include anxiety and depressed or irritable mood, these treatments help people realize their feelings are temporary and help them cope with these, rather than be controlled by them. Secondly, ACT is another behavioral therapy that encourages individuals to accept their thoughts and emotions without resistance or guilt [32]. It combines mindful- ness with the practice of self-acceptance. ACT encourages individuals to confront uncomfortable emotions, refrain from overreacting to them, and not avoid situations that trigger them [33], opposite to CBT. Research has shown that ACT is effective for smoking cessation, also delivered through the telephone [34]. Thirdly, DTT helps develop a set of skills for individuals to respond in a healthy way during distressing situation where they might not have the control [35]. However, studies do not show a clear improvement of smoking cessation success due to DTT [36]. Finally, yoga has shown promising results as adjunctive treatment for smoking ces- sation by alleviating nicotine withdrawal symptoms and improving negative affect, attributed to the benefits that aerobic exercise offers [37, 38]. As the landscape evolves, new and more accessible alternatives of advice and counsel- ing emerge, including mobile health technologies, from now on referred as mHealth. 9 2. Background mHealth are mobile applications used to deliver healthcare or disseminate health- related information [39]. As over 3.7 billion people had smartphones [40] and more than 250 billion mobile apps were downloaded in 2023 [41], these technolo- gies promise to significantly transform cessation strategies by making support, such as the cognitive therapies previously explained, readily available to those aiming to quit both smoking and snus. 10 3 Theory 3.1 Adopted Design Methodologies This section provides an insight into the theoretical basic of the methodologies uti- lized when designing the mobile application in this study. Drawing from principles rooted in the Service Design (SD) methodology and the Persuasive Technology (PT) framework, the adopted approach integrates various functionalities aimed at enhanc- ing user engagement and influencing behaviors effectively. Furthermore, the visual aspect of the mobile application follows the User Interface (UI) design principles to ensure that the user experience is both intuitive and aesthetically pleasing. In this way, this section clarifies the design decisions made and shows how the methodolo- gies shape the mobile application’s overall design. 3.1.1 Service Design for the Design of mHealth Applications mHealth applications are shaping a new healthcare paradigm where information re- lated to individuals’ health is easily accessible and ubiquitous [42]. As previously in- troduced, mHealth offers a promising avenue for delivering behavioral interventions, such as supporting snus cessation efforts. The development of these applications em- ploys diverse methodologies [43], including the SD methodology. SD is an approach to designing services that considers both the needs of the customer and the needs of the business to create quality service experiences [44]. This approach is based on the design thinking (DT) methodology, which applies a user-centric, solution-oriented strategy for solving complex challenges [45]. It has been used in the development of various mHealth applications [46, 47, 48]. In this way, it emphasizes a creative and user-centred process to design new services, including digital applications. The SD process uses research, prototyping, and a set of visualization tools to create the necessary characteristics of a product that meet the user needs [44]. These core tools are divided in three main groups during the design and development process of the product or service [82]: 1. Research: Different guidelines are provided to perform different types of re- search, such as preparatory research and autoethnography, and several tools are described to interpret the raw collected data, including key insights, job- to-be-done, user stories, personas, journey maps, and system maps. The ones employed on this project are further explained in the 4. Methods section. 11 3. Theory 2. Ideation: SD contains tools for both generating new ideas for the service or product that is being created, and then filter and arrange them to keep and further develop the promising ones. 3. Prototyping: In the SD process, prototyping help to identify important as- pects of a new service concept and explore different alternative solutions that are evaluated to see if they work in the real world [44]. SD offers various mechanisms to translate ideas into a tangible product, enabling early and cost-effective validation of its efficacy in real-world scenarios. These include several levels of realism of the prototype. For example, for a software product, it offers tools from idea sketching to interactive click-models. 3.1.2 Persuasive Health Technology Although individuals may feel motivated at first when quitting snus, it is not an easy process due to the withdrawal symptoms that come with nicotine addiction. In addressing this, PT plays a crucial role in facilitating changes in snus usage be- haviors. This technology, which forms the foundation of the functionalities in the mobile application designed in this study, employs non-coercive methods to alter user behaviors or attitudes, proving valuable across different fields, including public health [49, 50]. In health domain, through interactive digital platforms, ranking from desktops and internet services to mobile devices; persuasive health technol- ogy (PHT) targets health-related behaviors, aiming to enhance health outcomes or manage diseases effectively to maintain or improve a person’s health-status [51, 52]. PHT, provided particularly through mHealth applications, is an effective tool to promote health as well as prevent and manage diseases. To do so, it includes a wide range of activities like encouraging physical activity, promoting healthy eating, and facilitating tobacco cessation. For this project, PHT aimed at tobacco cessation is especially relevant. These tech- nologies often incorporate cognitive approaches to modify users’ attitudes towards tobacco use [50], being CBT one of the most established methods, as previously introduced. The Persuasive Systems Design (PSD) framework [51] guides the design of persua- sive systems, outlining the design principles across four main areas: Primary Task Support, Computer-Human Dialogue Support, System Credibility Support, and So- cial Support (see further detail in section A.2. of the Appendix). These principles guide the definition of this project’s app functionalities that align with snus cessa- tion, ensuring an effective mHealth solution [26]. Especially focus is given to the Social Support part, where the system motivates users through social influence [53]. Interpersonal relationships are crucial for both psychological and physical well-being and they can assist individuals in managing stress, motivating behavioral changes, and sustaining new habits [54]; three key elements for snus cessation. Several studies have shown that a supportive social environment improves the success of smoking cessation and prevents from relapse [55, 56]. 12 3. Theory Based on Fogg’s principles on mobility and connectivity [57], the system can employ various strategies to encourage users to change their behaviour. These include allow- ing users to observe others performing similar behaviors, comparing their progress, creating a sense of belonging to a group with shared goals, facilitating cooperation or competition among users, and offering public recognition for their achievements. Some of them are included in the app’s functionalities of this project. 3.1.3 User Interface Design Effective mHealth applications require not only the right functionalities but also a user-friendly presentation. This is where UI design principles become indispensable. UI design focuses on building interfaces in software and digital devices that are both aesthetically pleasing and easy to navigate [45]. To achieve this, it is essen- tial to define a clear navigational structure, incorporating standard app navigation components such as hamburger bars, tab bars, or navigation drawers. Additionally, following Paret’s principle that suggest that 80% of users typically use no more than 20% of available options [58], the number of functionalities offered on each screen should be kept simple. This principle is especially crucial when designing the home screen, where determining and prioritizing the most important features for users is key. The final app design should be customized for the target audiences, in this case, young people who use snus. While the design might draw inspiration from pop- ular social media platforms to resonate with the user base, it should also include health-specific adaptations [58]. These may include a simple design with calming white and smoothing colors to maintain user focus, consistent and friendly tone in textual content, health-specific icons for the application buttons, and motivational messages to promote a positive approach to the snus quitting process. Furthermore, micro animations, such as progress bars or interactive elements when clicking on buttons, can enhance user engagement and interaction within the application. This design aligns with the PSD model’s guidelines outlined above for an effective health intervention tool. 3.2 Artificial Intelligence Counseling in Health During recent years, AI has expanded its presence to the healthcare field, including its use in mental health management [59]. AI chatbots are already widely used for self-service in other industries and now they are being developed for therapeutic purposes, too. These chatbots are created combining big data, natural language processing, and machine learning algorithms to make them able to talk and guide individuals for different tasks [60]. In the context of mental health, traditional psychotherapy can be inaccessible and expensive, so AI chatbot therapists offer basic psychological tools in a more afford- able way [61]. These chatbots are used to offer advice and as a line of communication during treatment for mental health patients [62]. Numerous studies have explored 13 3. Theory the effectiveness of AI chatbots that treat diverse mental health conditions. For in- stance, XiaoNan, a chatbot powered by the open-source conversational AI "RASA"1 and based on CBT principles, was used effectively for self-help depression treatment among Chinese university students [63]. Another chatbot, Weabot2, has proven to be effective in helping individuals with conditions such as depression, anxiety, and substance abuse. It does so by adapting to users’ personalities and offering exercises to cope with these conditions. These studies highlight the potential of AI chatbots to address common mental health disorders, especially for unserved populations [60]. However, the ethical implications that integrating AI into therapy can create must be evaluated. Professional organizations should develop guidelines for assessing and regulating AI applications in mental health to ensure they complement professional care while emphasizing transparency, ethical use, and ongoing research on their im- pact and long-term effects [61]. Focusing on smoking cessation, AI-powered chatbot mobile applications have been developed like QuitBot [64]. QuitBot, based on scientifically validated content, com- bines conversations to guide users through the quitting process with the flexibility offered by the trained AI to answer the users’ questions about smoking. In this way, it provides personalized support that sets it apart from other existing apps. Nevertheless, the evaluation of the effectiveness of these AI-chatbots when assisting tobacco cessation is mixed and should be interpreted cautiously [65, 66, 67]. 3.3 Ethical Considerations In the process of designing a mobile application for snus cessation, it is key to estab- lish a clear and transparent communication with users regarding the purpose, use, benefits, and potential risks of the mobile application, especially considering that the users are likely to be young individuals. Additionally, the information and guidance provided to users about snus and addic- tion must be accurate and evidence-based. It should adhere to medical standards to ensure its veracity and safety in addressing nicotine addiction and cessation. This becomes particularly important in the context of AI counselling or user-generated content, where there is a risk of disseminating misinformation. Furthermore, the mobile application should employ respectful and non-manipulative strategies in its aim to engage users to enhance its effectiveness in assisting them in quitting snus. Positive incentives that do not negatively impact the users’ psycho- logical well-being should be used. Moreover, the design of the mobile application should be inclusive, catering to a broad user base, and it should incorporate multi- language support to enhance accessibility. Continuous improvement of the mobile application is also vital. This improvement should be guided by user feedback to 1Conversational AI Platform 2Woebot Health 14 https://rasa.com/ https://woebothealth.com/ 3. Theory maintain the effectiveness and relevance of the mobile application over time. During the interviews with potential end users, the interviewees are thoroughly informed of the purpose of such interviews, including the main objectives of the project and its status as a master’s thesis for Chalmers University of Technology. They are also notified about how their personal data regarding their snus usage will be used in the design of the mobile application and that it will be anonymously included in the project’s report. This ensures that participants can provide informed consent to participate in the interview process. 15 3. Theory 16 4 Methods This chapter outlines the methodology employed in this study, offering insights into the approaches used to research key aspects related to snus use and cessation. It also presents the methods employed in the overall design of the mobile application and their relevance to the project. The mobile application designed in this study is called ExSnus and will be referred to by this name throughout the document. A SD process was followed for the design of ExSnus to ensure that its design and functionalities truly resonate with its intended users. This decision was influenced by research showing that mobile applications developed without sufficient user and clinician input often fall short in quality [46, 48]. The process began with a review of academic literature to gather insights into existing mHealth tools targeting snus cessation and other treatments directed to nicotine addiction, as well as numerical data regarding snus consumption to have an idea of the potential end-users’ num- ber. In parallel, interviews were conducted with potential users to gain a deeper understanding of their experiences, perspectives, and needs related to snus cessa- tion. This knowledge informed the definition of the specific functionalities of ExSnus to aid snus cessation, guided by the PSD’s model principles. Subsequently, mock- ups were created to visually represent these features in an application prototype, starting with rough sketches during the ideation phase and culminating in a detailed digital prototype. The prototype then underwent an iterative improvement process, incorporating feedback from potential users. In this manner, end-users actively par- ticipated in providing valuable insights and validating the viability of ExSnus. This methodology is applied throughout the steps depicted in Fig.4.1. Figure 4.1: Project steps followed in the application design based on the Service Design process [11, 46]. 17 4. Methods 4.1 Research Approach The initial phase of this project involved conducting a comprehensive review of important factors related to snus use and cessation. This included examining demo- graphic information and understanding the physiological and cognitive impacts of snus. Additionally, interviews were conducted with college students who use snus to further explore their relationship with it. These insights guided the definition of the features of the ExSnus mobile application, aiming to address users’ vulnerabilities and boost their strengths as they embark on their journey to quit snus. 4.1.1 Preparatory Research In the initial phase of this study, which corresponds to Step 1 of the project frame- work following the SD process in Fig. 4.1, preparatory research is conducted to gain insights into the subject matter and similar existing products [68]. In this case, the research served to understand the current landscape of snus consumption and the existing approaches to help in its cessation, with a particular focus on existing mHealth applications. This literature study aims to provide a holistic understand- ing of the matter and identify potential techniques for snus cessation that could be addressed through the design of ExSnus (i.e., using theory as a contextual tool [69]). The literature study includes various sources, ranging from research articles and books to websites. The first stage is to profile individuals who use snus, quantifying their numbers and exploring their reasons to consume snus. Moreover, the physiological effects of snus on the human body, its addictive properties, and the reasons why individuals find it challenging to quit are also studied. In this manner, this first stage provides a contextual understanding of the issue ExSnus addresses, illustrating potential user behaviors and needs that are later represented as a persona. This stage is further informed through interviews with young snus users as later explained. Secondly, a review of current strategies employed to assist both smoking and snus cessation is conducted, with particular emphasis on existing mHealth applications related to snus cessation. The goal is, on the one hand, to understand cognitive methodologies for managing snus cessation withdrawal symptoms that could be in- tegrated into ExSnus and, on the other hand; to identify any gaps in these mobile applications that ExSnus could potentially address. By assessing the strengths and weaknesses of existing solutions, the effectiveness of the designed mobile application can be enhanced. Additionally, the possibility of adding an AI counselor and its effectiveness is studied. Finally, current tendencies in application design are explored to apply these design principles to ensure that ExSnus would align with user expectations and preferences, which are presented in depth in the following section. 18 4. Methods Throughout the literature study, each information source undergoes a rigorous eval- uation process to assess its quality and relevance. This assessment involves a metic- ulous examination of the studies’ content, an evaluation of the methodologies em- ployed, and an assessment of the source’s relevance to the research questions. 4.1.2 Interviews with Snus Users In addition to reviewing literature related to the causes of snus use and nicotine ad- diction, interviews were conducted with college students from Chalmers University in Gothenburg who use snus. The interview approach was chosen from the differ- ent research methods offered in the SD process alongside the preparatory research because it serves as an effective method to empathize with users, enabling a deep understanding of their values, perceptions, and experiences. Young university stu- dents were chosen for the interviews guided by the belief that a mobile application aimed at helping with snus cessation is more likely to be utilized by the youth . It is important to note that higher education seems to act as a protective factor against regular nicotine use [70, 71], so the answers to the same questions regarding snus consumption could differ among individuals with other educational backgrounds. The type of interview chosen is a semi-structured interview as there is an initial set of questions, but there is room for clarification or follow-ups, facilitating deeper exploration of interviewees’ comments and insights [72]. This approach allows for asking specific questions while remaining open to exploring the participants’ point of view. The interview’s initial set of questions covers various aspects related to snus use, addiction, motivations, and thoughts on cessation: 1. How long have you been using snus? 2. Why/How come did you start using snus? 3. What time do you use snus first time each day after waking up? 4. What time do you use snus last time each day before sleeping? 5. When do you use snus most during the day? Is it any trigger for you to use it? 6. Do you consider yourself addicted to snus? Why do you think so? 7. How much do you snus daily and how often do you snus daily? 8. Do you also smoke or did you smoke before? If so, how much and how often? 9. Why do you use snus? Do you feel like it helps you in some ways? 10. Do you know what snus contains? Do you consider that it can be dangerous for your health? 11. Do you think snus is a part of the Swedish culture? Do you feel the use of snus is regarded as something normal in society or something cool in your generation? 12. Have you thought about quitting snus or reduce the frequency or the amount of snus? What were the reasons behind your thought? 13. What do you think you need to help yourself to quit snus? 19 4. Methods These questions were asked to five students from Chalmers University of Technology who are current or former users of snus. The interviewees were four male partici- pants and one female participant in their twenties. Among these individuals, three are of Swedish nationality while the remaining two are international students. Subsequently, the interview responses undergo thematic analysis. Thematic analysis is a qualitative content analysis method employed to identify, analyze, and report patterns, known as themes, within the data [73]. The analysis involves dividing the data set into units of analysis [74], with each transcribed interview response serving as a unit of analysis in this project. Phrases are then grouped into meaning units, understanding by ’meaning unit’ sentences containing aspects related to each other through their content and context. These meaning units can be condensed to shorten them while persevering their core. Finally, the condensed meaning units are categorized into themes, each capturing an important pattern of the data related to the research questions. Several decisions need to be made before starting the theoretical analysis. Initially, it is crucial to define what constitutes a theme within the theoretical analysis frame- work. In this project, themes are selected with flexibility in mind, considering that they are not dependent on quantifiable measures, but rather capture important as- pects related to the overall research questions [74]. A theoretical thematic analysis is chosen as the type of analysis to perform because it focuses on providing a detailed examination of the most relevant aspects to define the functionalities of ExSnus. Furthermore, a semantic approach is adopted since the analysis does not extract any further meanings beyond what a participant has said. In this way, the answers of the interviews are categorized into different themes, as shown in the 5. Results section. To ensure the quality of the thematic analysis, the 15-point checklist pro- vided by [73] is followed (see section A.1. of the Appendix for the whole list). 4.2 Ideation of the Mobile Application Following the SD process [44], the data collected during the preparatory research and the analysis of the interviews with young snus users’ were used to define a per- sona. This persona represents a group of people characterized by shared interests, behaviors, demographics, or geographical traits [75]. In this project, it represents potential users of ExSnus and their needs regarding snus use and cessation. Sub- sequently, the functionalities of ExSnus are defined to address this persona’s needs. Inspiration is drawn from the already existing mHealth applications developed to aid snus cessation presented in the 5. Results section. The functionalities of ExSnus are represented through use cases, outlined then in a Unified Modeling Language (UML) use case diagram. Use cases are a tool used to understand, interpret, and organize the features of an application by illustrating how users interact with it [76]. They help outline who the users are, their goals, the steps they take to accomplish tasks, and how the sys- tem responds to these actions. Additionally, use cases serve to brainstorm potential 20 4. Methods misuses and malfunctions of the application and how to respond to them. When creating a use case, it should contain several key elements [77]: 1. System: The software being discussed within the context of the use case. In the case at hand, the ExSnus mobile application prototype. 2. Actors: They represent entities that exhibit behavior when interacting with the system. In the case at hand, it refers to the users, who are primary actors that initiate interactions with the system. For this project, the created persona is utilized as the user to formulate the use cases. 3. Scenario: It is a specific sequence of actions and interactions between actors and the system under discussion. It is also known as a use case instance usually numbered. 4. Use case: Use cases outlines both successful and unsuccessful scenarios that may arise when actors interact with the system. A UML use case diagram summarizes the actions that can be done by the actors and their interactions with the system, depicting a high-level representation of the relationship between use cases, actors, and system [78]. In conclusion, the process of outlining the functionalities of ExSnus involves inter- preting the raw data gathered from the preparatory research and from the interviews with young snus users. Main themes are extracted from this data that supports the creation of the persona to represent potential users of the mobile application. Use cases show the functionalities of ExSnus and are then summarized in the UML diagram. These specifications ensure a thorough understanding of the mobile ap- plication’s intended behaviors and user interactions, serving as a blueprint for the design phase. 4.3 Prototyping of the Mobile Application This section delves into the methodologies and techniques employed to create a tangible representation of ExSnus, ensuring its features and user interactions are ef- fectively realized before full-scale development. The process involves multiple stages, starting from initial sketching to interactive click modeling, each contributing to the refinement of the application’s design and usability. 4.3.1 Sketching Sketching plays a vital role in design process, facilitating translation of the func- tionalities of ExSnus into visual representations for testing them and ensuring their effectiveness. Widely recognized as a valuable method for idea generation in design field [79], sketching offers several advantages, including the visualization of concept designs, rapid ideation, and flexibility in refining the initial design of the application layout until it aligns with all the requirements. Additionally, it is the most cost- effective means of exploring design alternatives compared to other methods, such as 21 4. Methods prototyping. In this project, the sketching approach combines analyzing existing mobile applica- tions and their layouts, along with rough sketching to derive inspiration from them and learn from past design mistakes [80, 81]. This process entails translating the functionalities of ExSnus into different screen elements, such as buttons and text. Once the primary design is selected from the rough sketches, the Solution Sketch technique is employed for further refinement. This technique involves incorporating real text and clear titles for each screen sketch to produce a well-defined and elab- orated design concept [83]. Subsequently, this final sketch can be translated into more realistic designs using prototyping software. 4.3.2 Interactive Click Modeling Prototyping in the context of mobile application development involves creating de- tailed representations of applications that showcase their functionalities and designs without actual functional code [81]. These prototypes offer stakeholders insights into the application’s appearance and behavior, serving as a cost-effective way to evaluate the suitability of a solution before proceeding with full-scale development. Prototypes vary in fidelity, with initial wireframes being the quickest and most cost- effective. Wireframes provide the basic gray-scale layout and structure, outlining the application’s features as interface elements such as basic representations of buttons, text inputs, and screen layouts. They focus on structure and layout, excluding visual design details like content and color schemes [84]. Additionally, wireframes illustrate transitions between screens, offering an overview of the application’s features and user interactions [81, 85]. In this way, wireframes serve as digital translations of the initial on-paper sketches [81]. Lastly, the final digital prototype incorporates detailed design elements such as real images, button styles, font specifications, and responsiveness to different devices [85]. It should also address accessibility concerns like color blindness and legibility, ensuring an engaging flow to retain user attention [86]. This prototype is an interac- tive click model that is then validated through usability testing with potential end users of ExSnus in the validation step of the project. For creation of both the initial wireframe and the final interactive prototype, the project utilizes the software Figma1. Figma is a well-known and established web- based prototyping tool widely adopted in the design community which allows for design of interactive mobile application prototypes, offering clickable interface ele- ments and serving as a representation of a fully functional application. 1Figma: The Collaborative Interface Design Tool 22 https://www.figma.com/ 4. Methods 4.4 Usability Testing Usability testing evaluates the user experience to assess how intuitive a system is [87]. This process can involve qualitative or quantitative methods, be moderated or unmoderated, and conducted remotely or in person. In this project, an in-person approach that incorporates both qualitative and quantitative evaluation elements is chosen, aligning with the interview style to gain insight into users’ thoughts and feelings when using the prototype of ExSnus. First, participants are provided with a consent form (refer to section A.4.1 of the Appendix) to inform them how their information is going to be handled. Secondly, the participants fill a questionnaire (outlined in section A.4.2 of the Appendix) that collects basic demographic data relevant to the system being tested. This informa- tion is then taken into account when analyzing the results. The testing is moderated; participants are guided through the process and given spe- cific tasks to ensure all main functionalities of the application are explored. These tasks are detailed further in section A.4.3 of the Appendix. On the one hand, the qualitative analysis part consists of encouraging participants to verbalize their thoughts and expectations while using ExSnus, a method known as think-aloud protocol. Follow-up questions to some of their thoughts are asked while they complete the tasks. Think-aloud approach aims to reveal aspects of the interface that either delighted, confused, or frustrated the users [88]. After completing these tasks, two final questions are posed to participants, one of them focusing on the overall application’s functionality and the second one comparing the two specific features highlighted in the project; the AI assistance and the social part: 1. Which parts of the application do you think are the most helpful ones for the purpose of quitting or reducing snus use? Why? 2. Would you feel more comfortable using the AI chatbot or the forum to get support or information? Why? On the other hand, the quantitative analysis part uses the System Usability Scale (SUS) by John Brooke to quantify perceived usability through 10 questions [89]: 1. I think that I would like to use this system frequently. 2. I found the system unnecessarily complex. 3. I thought the system was easy to use. 4. I think that I would need the support of a technical person to be able to use this system. 5. I found the various functions in this system were well integrated. 6. I thought there was too much inconsistency in this system. 7. I imagine that most people would learn to use this system very quickly. 8. I found the system very cumbersome to use. 9. I felt very confident using the system. 23 4. Methods 10. I needed to learn a lot of things before I could get going with this system. The responses range from ’Strongly disagree’ to ’Strongly agree’ and it then gives a score between 0 and 100. Apart from the three documents they need to fill, including the consent form, the initial questionnaire and the SUS questionnaire; during the usability testing par- ticipants are provided with the interactive click model prototype, which effectively represents a functional application due to its clickable elements. The selected partic- ipants are from the target audience identified in the project’s initial phase ensuring that the feedback is reliable [58]. This group includes individuals from a previous group interview and other new university students. The results obtained from the test and feedback from participants are documented, analyzed, and utilized to refine the design of ExSnus. Usability testing is a crucial step as it ensures that the application prototype is effective and user-friendly before actually developing it. 24 5 Results 5.1 mHealth Applications and Cognitive Behav- ioral Therapy for Snus Cessation and Their Incorporation in the Functionalities of the Ap- plication Motivated by the rise of mHealth technologies as explained in the section 2.4 Snus Cessation Treatments and the subsection 3.1.1 Service Design for the Design of mHealth Applications, a review was conducted of the existing mHealth applications focused on snus cessation. While there are numerous mobile applications for smoking cessation such as the WHO QuitTobacco App1 and EasyQuit2, as well as other more general mobile applications directed to build healthy habits and routines like Habinator3, snus-specific cessation mobile applications are limited and relatively unknown. A summary of the identified snus cessation mobile applications can be found in Table 5.1. Table 5.1: Comparison of Snus Cessation Mobile Applications. Mobile appli- cation name Language Operating system Features Snus Stop 4 English Android 1. Information on money saved, snus spared, and life regained. 2. Details on withdrawal symptoms. 3. Graph tracking snus pouch usage over time. 4. 25 achievements related to snus pouches not consumed and money saved. 5. Setting saving goals. 1WHO QuitTobacco 2EasyQuit 3Habinator 4Snus Stop: Quit Dip & Nicotine 25 https://play.google.com/store/apps/details?id=com.who.quit.tobacco https://play.google.com/store/apps/details?id=com.herzberg.easyquitsmoking&hl=en_US&gl=US https://habinator.com/ https://play.google.com/store/apps/details?id=com.jc.stop_snus&hl=en_US 5. Results Application name Language System Features Quit Snus5 English iPhone 1. Information on money saved and snus spared. 2. 12 achievements related to days without using snus. 3. Reports on craving occurrences in various situations: alcohol, bored, coffee, driving, food, love, morning, party. 4. Setting saving goals. 5. Calculation of health-related ben- efits. 6. Breathing exercises. DipQuit: Sluta Snusa 6 Swedish iPhone 1. Information on money saved and snus spared. 2. Achievements related to days without using snus and money saved. 3. Calculation of health-related ben- efits. 4. Live chat with other users. Sluta Snusa - Bli Miljonär7 Swedish Android 1. Information on money saved and snus spared. 2. Allows multiple users on the same device. Snuskollen8 Swedish Android 1. Provides statistics on snus usage by hour of a day and days of the week. 5Quit Snus 6DipQuit: Sluta Snusa 7Sluta Snusa: Bli Miljonär 8Snuskollen 26 https://apps.apple.com/us/app/quit-snus/id6444684039 https://apps.apple.com/se/app/dipquit-sluta-snusa/id1059270152 https://play.google.com/store/apps/details?id=se.hv.rickardborjesson.snus&hl=sv&gl=US https://play.google.com/store/apps/details?id=com.snuskollen&hl=sv&gl=US 5. Results Application name Language System Features Snusfri9 Swedish iPhone 1. Information on money saved and days without using snus. 2. Ability to create a contract to quit snus. 3. Achievements related to days without using snus or personal goals. 4. Audio exercises for mindfulness. Slutta10 Norwegian, English Android 1. Information on money saved and days and hours without using snus. 2. Sharing option of money saved or time without using snus. 3. Link to a Norwegian webpage with advice and tools to change habits. 4. Add a ’Call Friend’ to call when you need to talk to someone. 5. Tips offered when struggling with cravings. 6. Add a motivational photo. 7. Achievements related to days without using snus 8. Breathing exercises. It is worth to highlight that while some snus cessation mobile applications provide information on health regained, this information often lacks scientific backing, a situation that is not unique to snus applications and has been observed in smoking cessation applications as well. For instance, Haskins et al. [90] found that out of 50 smartphone applications for quitting smoking recommended by the app stores, only two had scientific support. ExSnus incorporates some of the features found in the existing snus cessation mobile applications, including information on money saved, achievements related to snus not used, reports on cravings, and statistics on snus use. However, unlike these mobile applications, it also includes social features and an AI chatbot, along with more scientifically-based information on the withdrawal symptoms and the existing therapies explained in subsection 2.4 Snus Cessation Treatments. Moreover, it pro- 9Snusfri 10Slutta 27 https://apps.apple.com/se/app/snusfri/id762776939 https://play.google.com/store/apps/details?id=no.helsedir.slutta2020&hl=no&gl=US 5. Results vides deeper insights on the users’ feelings and activities that trigger cravings and tips to address them. Another important aspect is the effectiveness of these applications that help users overcome their addictions. Research studies have explored the efficacy of applica- tions designed to aid smoking cessation [90, 91, 92, 93], but similar studies specific to snus cessation mobile applications are currently lacking. The collective findings regarding smoking cessation applications suggest that they are helpful, either in- dependently or when combined with face-to-face assessments or online programs. This is particularly true in high-income countries with established tobacco control measures, media campaigns, and educational efforts. From the few applications that have given information about their quality and reliability, the reported quit rates for smoking cessation applications range from 12.5% to 51.5% [94]. Their success is mainly attributed to their ability to reach a wide audience at a minimal cost, making them more accessible to treatment-seeking individuals compared to other cessation interventions. When it comes to CBT, previously introduced as one of the most common cogni- tive approaches to help with smoking cessation; studies have tested CBT delivered through phone or computer platforms for various mental health conditions, includ- ing depression and anxiety disorders [95, 96]. These studies have shown that digital CBT interventions can deliver efficient and practical healthcare, especially to indi- viduals who might otherwise remain untreated. Furthermore, mobile applications for smoking cessation that incorporate CBT features have been associated with higher user engagement [97, 98]. Key features of these applications such as having a quit plan, tracking progress, and offering audio-visual content and sharing capabilities are highly accepted and utilized by the users [93]. Thus, these CBT features are included when defining the functionalities of ExSnus. In summary, research supports the effectiveness of both smoking cessation appli- cations and CBT delivered through digital platforms for quitting smoking and ad- dressing mental health conditions, particularly in high-income countries. These findings highlight the potential of technology-driven interventions to promote be- havioral change and expand healthcare accessibility, which can be applied to snus cessation as well. 5.2 Interviews Analysis From the theoretical analysis of the interviews, the main meaning units extracted from the answers that were similar among the interviewees are the following ones: 1. The interviewees were introduced to snus at parties or by friends. 2. All the interviewees that consider themselves addicted always start their day with snus, using it for the first time within the first hour of waking up. 3. Use snus to focus on study or work as it makes the interviewees feel relaxed. 28 5. Results 4. All the interviewees that consider themselves addicted feel anxiety when not using it. 5. Lack of knowledge of what snus exactly contains, but a slight sense that it is dangerous. 6. Snus is regarded as a part of the Swedish culture for the majority of the interviewees, or at least its use is regarded as normal for everyone. 7. The interviewees’ main concerns regarding their snus use is related to health and economical aspects. 8. How do the interviewees think a mobile application can help quit snus varies for each person. They are considered to define the use cases of the app: (a) Identify situations that trigger snus use to avoid them and have alterna- tives to those triggers to handle cravings. (b) Share the journey of quitting with friends. (c) Rewards when not using snus. (d) Combine with medication when addiction is stronger. 9. Some of the interviewees were skeptical when asked if AI could help them in the journey of quitting snus. Several core themes that highlight the psychological, social, cultural, and health- related dimensions of snus consumption can be summarized from these meaning units to provide a more integrated understanding of the main issues related to snus usage and cessation, depicted below. From these themes, it becomes clear that addressing snus usage through the designed mobile application requires considering the social influence, addressing the addiction and perceived benefits, and enhancing awareness of health risks. 5.2.1 Social Influence and Cultural Normalization Snus usage is a socially influenced behavior, deeply integrated in Swedish daily life. The role of friends and social gatherings in introducing snus, along with its normal- ization within the Swedish culture, creates a supportive environment for its contin- ued use. This influence highlights the importance of addressing snus considering the social and cultural context. 5.2.2 Addiction and Use On one hand, the routine of using snus right after waking up and the associated anxiety without it, points to a physical and psychological dependency. On the other hand, the use of snus to enhance focus and relaxation suggests that users perceive immediate, functional benefits, which may reinforce the habit despite the awareness of potential addiction. Therefore, an alternative must be provided for the functional benefits given by snus usage to encourage its cessation. 5.2.3 Health Concerns and Motivations for Cessation Despite individuals not knowing detailed information about the contents and risks of snus, they still perceive it as health risky, which acts as a significant motivator 29 5. Results for quitting. This limited awareness and health concerns are a critical area for intervention through the mobile application, where increasing knowledge about the risks could strengthen the motivation to quit, particularly when coupled with the economic incentives to reduce or stop its use. 5.2.4 Cessation Support and Technology Skepticism The difference among the answers to which functionalities of the application help each interviewee indicate the diverse needs among users in their quitting journey. Additionally, the skepticism towards AI assistance needs to be considered when deciding whether to add it. 5.3 Persona A persona, depicted Fig.5.1, was created using the insights gathered from the litera- ture study and interviews. This persona embodies a university student from Sweden and serves as a representative model of potential app users. His goals, preferences, and challenges are considered when creating the use cases that define the app’s functionalities. 14 15 16 5.4 Use Cases In illustrating the use cases, the software serves as the system, portraying the func- tionalities of the ExSnus mobile application and considering possible alternative scenarios. Table 5.2: Use Case 1: User Creates a Profile Use Case 1 Create Profile Use Case Goal To enable Gustav Olsson to create a personal profile on ExS- nus, which is essential for tailoring the application’s features to his specific preferences. Primary Actor Gustav Olsson, 22-years old student. Preconditions 1. The user, Gustav, has downloaded ExSnus on his phone. 2. Gustav has a stable internet connection. 3. Gustav has all the necessary information ready, such as his email address, a desired username, and personal goals related to quitting snus. 14This Person Does Not Exist - Random Face Generator 1520 User Persona Templates 16Vector Icons and Stickers 30 https://this-person-does-not-exist.com/en#google_vignette https://visme.co/blog/user-persona-template/ https://www.flaticon.com/ 5. Results Basic Scenario 1. Gustav opens ExSnus on his phone. 2. The application displays a welcome screen containing a congratulating phrase for having started the journey to quit snus and an option to "Start the journey". 3. Gustav selects the "Start the journey" option. 4. The application prompts Gustav to enter his personal information, including email address and a secure pass- word. Additionally, he is asked to provide his name, which the app will use in future interactions to create a more personalized experience. Finally, he must ac- cept the Terms and Conditions, as well as the handling of his personal data, to be able to continue with the profile creation. 5. The application then asks Gustav to input additional information relevant to quitting snus, some of which is mandatory including his daily snus usage, how much a snus can costs, and preferred quit date (today or a future date). Additionally, there is optional information that can be added to tailor his quitting plan. This includes the number of prior quit attempts and a questionnaire to measure his addiction level. Finally, he can option- ally personalize the experience on the app to motivate himself further, including his motivation for quitting, a financial saving goal, and what he intends to do with the saved money. 6. Gustav fills in the details. 7. The application creates Gustav’s profile and shows a screen that informs him of the amount of money he could save in a year, the number of snus pouches he would avoid, and the key health benefits he could gain. If Gustav entered his motivation, the application reaf- firms how achieving his goals aligns with these benefits. Furthermore, the application suggests a tailored quit- ting plan for Gustav: • If he obtains a high score on the addiction test and/or has previous failed quit attempts, ExSnus recommends Nicotine Replacement Therapy (more information can be obtained once inside the app) and gradually reduce snus usage. • If he obtains a low score on the addiction test and does not have previous failed quit attempts, ExSnus recommends Cognitive Behavioral Ther- apy and/or mindfulness techniques (more informa- tion can be obtained once inside the app) and snus use can be reduced more abruptly. 8. Gustav is directed to the main dashboard, where he can start using various features to assist in his goal of quit- ting snus. 31 5. Results Continued on next page Alternative Scenarios 1. If Gustav enters an email address that is already in use, the application informs him and prompts him to either log in or use a different email address. 2. If Gustav’s internet connection is lost during the profile creation process, the application saves the entered in- formation and prompts Gustav to complete the process once the connection is restored. 3. If Gustav decides not to provide some optional infor- mation, the application allows him to skip certain steps but reminds him that providing more information can lead to a more personalized experience. Table 5.3: Use Case 2: User Records Snus Usage Use Case 2 Record Snus Usage Use Case Goal To allow Gustav to log each instance he uses snus, capturing his emotional state and the context of the activity during the usage, to provide support and insights of his quitting journey. Primary Actor Gustav Olsson, 22-years old student. Preconditions 1. Gustav has a profile and has logged into ExSnus. 2. Gustav knows how to register snus usage on ExSnus. Basic Scenario 1. Gustav uses snus and wants to register it on ExSnus. 2. Gustav opens ExSnus and clicks the ‘add’ button from the main menu. 3. The application directs him to a new screen where he can select several options to register, including having taken snus and having overcome a craving. 4. Gustav selects the ‘Snus use’ option and is then pre- sented with a list of emotions to choose from, reflecting what he was feeling when he decided to take snus (e.g., stressed, bored, sad). 5. After selecting the emotion, he can also indicate the activity he was engaged in when taking the snus from a list (e.g., studying, drinking, socializing). 6. Gustav submits his inputs, and the application logs the information provided to display it in the dashboard. 32 5. Results Alternative Scenarios 1. If Gustav accidentally clicks the ’add’ button, there should be an option to cancel the entry. 2. If Gustav is unsure about how he felt or what he was doing, the selection should be optional. Following this choice, the application could provide a gentle reminder for him to pay more attention to his emotions and activ- ities during future instances to help recognize triggers. 3. If the application fails to save Gustav’s entry due to a technical issue, it should notify him of the error and prompt him to try again. Table 5.4: Use Case 3: User Records Craving Overcame Use Case 3 Record Craving Overcame Use Case Goal To allow Gustav to log each instance he overcomes a snus craving, capturing his emotional state, the context of the ac- tivity during the craving, and any method he used to resist the craving, to provide support and insights of his quitting journey. Primary Actor Gustav Olsson, 22-years old student. Preconditions 1. Gustav has a profile and has logged into ExSnus. 2. Gustav knows how to register overcoming a craving on ExSnus. 33 5. Results Basic Scenario 1. Gustav experiences a snus craving but successfully re- sists it and wants to register in on ExSnus. 2. Gustav opens ExSnus and clicks the ‘add’ button from the main menu. 3. The app directs him to a new screen where he can select several options to register, including having taken snus and having overcame a craving. 4. Gustav selects the ‘Overcame craving’ and is then pre- sented with a list of emotions to choose from, reflect- ing what he was feeling when he felt the craving (e.g., stressed, bored, sad). 5. After selecting an emotion, he can also indicate the ac- tivity he was engaged in at the time of the craving from a list (e.g., studying, drinking, socializing). 6. Next, Gustav can select how he managed to overcome the craving, including default choices like breathing ex- ercises or drinking water. There is also an option for Gustav to add and save new methods that have worked for him, including the use of nicotine medication or other personal strategies. 7. Gustav submits his inputs, and the application logs the information provided to display it in the dashboard. Alternative Scenarios 1. If Gustav accidentally clicks the ’add’ button, there should be an option to cancel the entry. 2. If Gustav is unsure about how he felt or what he was doing, the selection should be optional. Following this choice, the application could provide a gentle reminder for him to pay more attention to his emotions and activ- ities during future instances to help recognize triggers. 3. If the application fails to save Gustav’s entry due to a technical issue, it should notify him of the error and prompt him to try again. 34 5. Results Figure 5.1: Persona that represents a potential user of the project’s app. The image of the persona was generated using the website This Person Does not Exist11. The layout was created based on a template from Visme12and the icons were from Flaticon13. 35 5. Results Table 5.5: Use Case 4: User Visualizes Dashboard Use Case 4 Visualize Dashboard Use Case Goal To provide Gustav with a visual representation of his progress in quitting snus, including data on his usage, emotional trig- gers, activities, savings, and goal (if provided) progress, to motivate and guide him through his quitting journey. Primary Actor Gustav Olsson, 22-years old student. Preconditions 1. Gustav has a profile and has logged into ExSnus. 2. Gustav has registered snus used and cravings overcame in ExSnus. 3. Gustav has set a quit date and possibly a financial goal and motivation related to quitting snus. Basic Scenario 1. Gustav opens ExSnus, and the main screen contains the dashboard. 2. The dashboard displays his avatar, which, when clicked, takes him to his profile. Below the avatar, there are the main goals of Gustav, if provided. These goals include his set quitting date and his motivation for quitting, which is prominently displayed as a reminder and source of inspiration. Additionally, the saved money from not purchasing snus is also displayed, along with a progress bar toward his financial goal if he has set one. 3. Below this information, a graph shows his snus con- sumption over the week, with an option to switch to a monthly view. 4. Pie charts provide insights into his emotional states and activities at times when he typically uses snus, aiding him in identifying patterns and triggers. Moreover, the main activities that help him overcome cravings are also displayed for him to learn what works for him to reduce snus use. 5. At the end of the week, the graph includes a summary comparing his current week’s snus usage to the previous week, informing of the percentage of increase or decrease of snus use compared also to his consumption before starting the quitting process. If there is an increase in usage, the application provides a message encouraging Gustav to review and utilize his strategies for overcom- ing cravings. 36 5. Results Alternative Scenarios 1. If Gustav has not logged any snus usage or craving over- came, the application indicates him that there is a lack of data and encourages him to log activities to get per- sonalized insights. 2. If Gustav has reached his quit date, the dashboard up- dates to celebrate his achievement and transitions to support his maintenance phase, continuing to track his progress and emotional states. 3. If the application detects a significant improvement in Gustav’s snus usage patterns, the dashboard highlights this success, and the application offers congratulatory feedback, reinforcing positive behavior. Table 5.6: Use Case 5: User Visualizes Timeline Use Case 5 Visualize Timeline Use Case Goal To enable Gustav to view a comprehensive timeline of his quitting journey, showcasing his snus usage, cravings he over- came, milestone achievements, withdrawal symptoms, and health improvements, to motivate and provide insights into his progress. Primary Actor Gustav Olsson, 22-years old student. Preconditions 1. Gustav has a profile and has logged into ExSnus. 2. Gustav has registered snus used and cravings overcame in ExSnus. 37 5. Results Basic Scenario 1. Gustav accesses the timeline feature within the applica- tion from the main menu. 2. The timeline displays a chronological sequence of events: each instance of snus usage, moments when he overcame a craving, and the achievement of key milestones (like 1 week, 1 month, and subsequent months without snus). 3. Alongside these events, there is another tab that switches to a different timeline showing withdrawal symptoms extracted from scientific literature, helping Gustav understand the correlation between his physi- cal experiences and his quitting journey. This second timeline also illustrates health improvements over time, based on general expectations of recovery and healing from snus usage. 4. Gustav can interact with the timeline, clicking on events or milestones to get more details or insights, including the details of the logged snus use and craving overcame, and more in-depth information about health benefits and withdrawal symptoms. 5. When clicking on a withdrawal symptoms, more in depth information about the symptom extracted from scientific literature is displayed. Alongside it, there is educational content on nicotine replacement therapy and mindfulness therapy with links to reliable sources offering further information online about these thera- pies. Alternative Scenarios 1. If Gustav has not logged any recent activity, the time- line only shows milestones, withdrawal symptoms, and health benefits if existing for that week. 2. In case of reaching a new milestone, the application con- gratulates Gustav, reinforcing his achievements and mo- tivating him to continue his journey. 38 5. Results Table 5.7: Use Case 6: User Engages with Social Features Use Case 6 Engage with Social Features Use Case Goal To enable Gustav to share his quitting journey achievements and statistics with others, both on external social media plat- forms and within the mobile application’s community forum, making him feel supported. Primary Actor Gustav Olsson, 22-years old student. Preconditions 1. Gustav has a profile and has logged into ExSnus. 2. Gustav has achieved milestones or statistics that he wants to share. 3. Gustav has other social media and is willing to engage with the mobile application’s forum. Basic Scenario 1. The application offers Gustav options to share his achievements and statistics on external social media or on the application’s dedicated forum from the dash- board or the timeline. 2. If Gustav chooses to share on external social media, the application generates a shareable graphic or mes- sage highlighting his achievements, which he can post directly to his social media accounts. 3. If Gustav opts to share within the ExSnus’s forum, he can create a new post, attach his achievements and statistics, and add any additional text, like a message sharing his experiences or asking for advice. 4. Gustav can also create a new post by accessing the fo- rum from the main menu and then clicking on the but- ton to create a new post at the top of the forum’s screen. 5. Other users can view Gustav’s posts in the forum, re- act to them, and engage in conversation, offering sup- port, sharing their experiences, or providing tips, on the post’s comment section. 6. Gustav can visualize on the forum’s screen the posts created by other users, react to them, and engage in conversation. 39 5. Results Alternative Scenarios 1. If Gustav starts a post by accident on the forum, he can cancel the process. If he wants to edit or delete a post that is already created, there are tools to do so. 2. If Gustav faces technical issues while trying to share his achievements, the application provides troubleshooting tips and allows him to save his post to share later. 3. If Gustav receives negative feedback or encounters a dis- couraging interaction on the forum, the application of- fers tools for reporting inappropriate behavior. Table 5.8: Use Case 7: User Manages Their Profile Use Case 7 Profile Management Use Case Goal To enable Gustav to personalize his profile settings, including his quit date, motivational message, financial goal, notifica- tion preferences, light or dark mode, and avatar. Primary Actor Gustav Olsson, 22-years old student. Preconditions 1. Gustav has a profile and has logged into ExSnus. 2. Gustav knows how to access his profile. 40 5. Results Basic Scenario 1. Gustav taps on his avatar on the dashboard to access his profile settings. 2. In the profile section, he sees several options: • Modify the end date for snus use. • Update his motivational message. • Adjust his financial saving goal. • Turn notifications on or off. • Switch between light mode and dark mode. • Change his avatar. • Access and adjust other basic tools and settings, such as the app’s language, and the account email and password. 3. Gustav selects and modifies his end date for quitting snus, ensuring it reflects his current goals. 4. He updates his motivational message to something that currently resonates with his journey. 5. Gustav adjusts his financial saving goal based on his progress or changing aspirations. 6. He chooses his preferred notification settings and switches to dark mode for a more comfortable visual experience in low-light environments. 7. Gustav changes his avatar to a new image that he feels represents his journey or current mood. 8. After making the desired changes, Gustav saves his up- dated settings, which are immediately reflected in his app experience. Alternative Scenarios 1. If Gustav faces technical issues while trying to update his profile, the application provides troubleshooting tips. 2. If Gustav is unsure about the implications of certain settings (like turning off notifications), the application provides brief descriptions explaining what each setting does and how it might affect his experience and progress. 41 5. Results Table 5.9: Use Case 8: User Receives Notifications Use Case 8 Receive Notifications Use Case Goal To provide Gustav with timely and relevant notifications about his milestones, forum engagement, and progress up- dates, encouraging continuous engagement and motivation throughout his quitting journey. Primary Actor Gustav Olsson, 22-years old student. Preconditions 1. Gustav has a profile and has logged into the app. 2. Gustav has enabled notifications in his profile settings. Basic Scenario 1. If Gustav reaches a milestone (e.g., one week without snus), ExSnus sends a notification congratulating him on his progress and encouraging him to review his health benefits and withdrawals. This notification takes Gus- tav to the ‘Timeline’ screen. 2. When another user interacts with his post or comments on the forum, Gustav receives a notification, prompting him to view the interaction and engage with the commu- nity. This notification takes Gustav to the ’Community’ screen. 3. At the end of each week, ExSnus notifies Gustav that a summary of his weekly progress is available, encouraging him to review his achievements and areas for improve- ment. This notification takes Gustav to the ’Weekly report’ screen. 4. As Gustav approaches his set quit date or reaches it, ExSnus sends a notification reminding him of the upcoming date, reinforcing his commitment to quit- ting. This notifications takes Gustav to the ’Dashboard’ screen. 5. If Gustav is close to reaching his financial goal related to saving money by not purchasing snus or reaches it, ExSnus notifies him to acknowledge his progress and motivate him further. This notifications takes Gustav to the ’Dashboard’ screen. 6. The chatbot periodically sends notifications to Gustav asking about his well-being to prompt a conversation. This notification takes the user to the ‘Chatbot’ screen where the question appears written in the chat. 42 5. Results Alternative Scenarios 1. If Gustav chooses to disable notifications temporarily, the application stops sending notifications. Table 5.10: Use Case 9: User Chats with AI Counselor Use Case 9 Chat with AI Counselor Use Case Goal To provide Gustav with immediate support and guidance through an AI-driven chat feature, helping him address con- cerns, receive advice, and maintain motivation throughout his quitting journey. Primary Actor Gustav Olsson, 22-years old student. Preconditions 1. Gustav has a profile and has logged into ExSnus. 2. Gustav knows how to access the AI counselor chat. Basic Scenario 1. Gustav feels the need for support or has questions about his quitting process. 2. He opens ExSnus and clicks on the chat icon to initiate a chat with the AI counselor. 3. The AI counselor greets Gustav and encourages him to share what is in his mind or ask questions. Suggested questions are also available to click. 4. Gustav interacts with the AI chatbot, sharing his thoughts, concerns, or questions, by writing on the chat or using his voice. 5. The AI chatbot processes Gustav’s input and provides feedback, advice, or motivational messages based on his inquiries. 6. The conversation continues as needed to support Gus- tav’s quitting journey. 7. Gustav ends the chat session when he feels satisfied with the interaction or has received the help he needed. 8. Alternatively, the chatbot sends regular notifications to Gustav asking about his well-being, if enabled the func- tion. 43 5. Results Alternative Scenarios 1. If the AI counselor cannot adequately address Gustav’s concerns due to the complexity or specificity of the is- sue, the application should suggest Gustav to seek ad- vice from a human professional or provide resources for further assistance. 2. If Gustav does not enable the application’s notifications, the chatbot does not send prompts asking about his well-being. A UML case diagram, depicted in Fig.5.2, was created to represent the functionalities defined in the use cases, as well as the interactions between the users of ExSnus and the ExSnus system itself. Several existing diagrams of similar processes from other studies were used as inspiration, including the diagram of a forum discussion [99], a chat bot [100], and mobile application’s notifications [101]. 5.5 App Design After defining the functionalities of ExSnus through use cases, these were translated into visual elements across various screens. Initially, rough hand-drawn sketches were made to capture all the essential features to ensure that ExSnus contained every defined functionality. These sketches were then translated into a digital wireframe. This wireframe include basic gray-scale screen components like buttons, main text, image placements, and various screen statuses such as error messages as well as all the inter-screen connections, showing the logic behind the mobile application’s functioning. Finally, the main screens were refined into visually appealing designs to be used as the interactive click model during usability testing. 5.5.1 Sketches The initial sketches were drawn to fulfill the requirements of each use case. These sketches contain the main basic screens and the connections between them, as well as some comments of special cases or design elements. An example can be found in Fig.5.3. The rest of sketches are displayed in section A.3.1 of the Appendix. 5.5.2 Wireframe and Functionalities of ExSnus Depicted by Screens The created wireframe connects all existing screens in low-level detail through the buttons