App features that could promote engagement
| Feature | Brief description |
| Gamification | Attractive gamified quitting journey with continuity story line and variable plot |
| Personalisation | Make the app as interactive as possible (eg, tailored feedback); promote engagement by customised message push notification based on users’ own smoking behaviour |
| Professionalisation | Make the app looks professional with scientific endorsed content |
| Personification | Establish a ‘rapport’ between the participants and healthcare providers |
| Social interaction and support | Provide a platform for interactions among the participants, their quitting sponsors and healthcare providers. Linking with social networking software that is, WeChat |
| Transparency and realistic expectations | Set up clear expectations concerning how the app will be used |
| Shaping | Keep demands of the participants to a minimum |
| Design for curiosity | Unluck some information each day during preparation; present new information each time the app is accessed |
| Instant feedback | Provide instant feedback (eg, tips for craving, progression statistics) |
| Rewards | Provide users with a rewarding experience when they visit the app |
| Positive recognition | Record quitting time and provide recognition and encouragement by gamified achievement system, visualise health and finance improvement |
| Visual cues and dashboards | Use as many as possible images to convey information |
| Structure sections | Break complex tasks into small steps |
| Session time | Keep login sessions brief (each session takes less than 1 min of the users' time) |