Introduction: System design

• Smiletracker uses a built-in webcam to make it easy to capture moments that elicit smiles while using a computer • When you smile, Smiletracker recognizes it and saves both the image of your face and what you were looking at. • You can easily review what made you smile and share it! • Based on positive psychology research, we hypothesize that the act of reviewing smile-eliciting content will improve positive affect, and consequently, overall wellbeing. • We conducted a preliminary user study to test this hypothesis, as well as to gather feedback on the initial design. • Users log in to the site using their Facebook account, and are taken to a personal profile page (Fig 1).