Caffeine Curfew is a native iOS and WatchOS app that helps users track caffeine intake, hydration, and master their sleep. It allows tracking the active half-life decay of caffeine, integrates with Apple Health, features Homescreen Widgets, and provides sleep analysis tools to enhance understanding of productivity and rest. The app prides itself on listening to users and iterating quickly, offering a comprehensive solution for managing caffeine impact and improving sleep quality.