Onset - Caffeine Tracker

Onset is a private caffeine timing tracker. Log coffee, espresso, matcha, tea, energy drinks, cold brew, or custom caffeine, then see how much may still be active in your system and how much could carry into bedtime. No account. No cloud. No ads. Your logs stay on your phone. WHAT ONSET DOES • Fast caffeine logging Repeat a recent drink, pick a preset, or add custom caffeine in a few taps. • Active caffeine estimates Onset uses caffeine half-life math to estimate what may still be active after each log. • Bedtime carryover See an estimate of how much caffeine may still be active at your bedtime, so timing is easier to understand before the night gets away from you. • Timing patterns Review daily, weekly, monthly, and yearly views, including time-of-day patterns and top caffeine sources. • Private by default Onset is local-only. There is no account to create and no cloud sync to manage. WHAT ONSET ISN’T Onset is not a medical tracker, sleep diagnosis tool, or habit coach. There are no streaks, goals, warnings, or moralizing. It is a simple mirror for your caffeine timing: what you logged, what may still be active, and what patterns are showing up over time. Built by one person. Feedback is welcome: inder@doodlestudio.io