Clockwork is an app that guides women in the postpartum period/elders after retirement to regulate their biological clock by self-reporting their daily behaviors in 30mins base. The app is a behavioral health program that harnesses the knowledge of the circadian timing system to improve health and performance. By allowing users to report daily behavior patterns and to track back their behavioral history, ClockWork optimizes the user’s sleep patterns, light-dark exposure, eating, and physical activity based on circadian principles.