Abstract
Many self-trackers lose interest in, disengage from and ultimately withdraw from tracking. Reasons for this include poor motivation, unmet expectations and difficulty in attaining daily goals. To support users in reflecting on their goals more realistically, we developed FitReflect, an app that moderates physical activity goals by factoring in users' confidence in achieving the goals. The app also encourages users to reflect on their goals regularly and think about the factors affecting their achievement. We conducted a 4-week field experiment where we trialled the app with fourteen Fitbit users. We found that, compared with a non-moderated goal condition, participants with moderated goals achieved their goals more often, got closer to them, and adjusted them more frequently. Crucially, they were also more satisfied with their physical activity. More frequent goal updates were key to align user goals with their confidence and capabilities in achieving them.