HalfLife Caffeine

Know your caffeine. Sleep better. HalfLife Caffeine is a free, science-based caffeine tracker for your Garmin watch. It models how caffeine decays in your bloodstream using a pharmacokinetic half-life 5.7 hours by default, and adjustable to your own metabolism, so you always know how much is still active, and when you'll be safe to sleep. Features At-a-glance tracking. See current caffeine level and time to sleep-safe right in the widget loop. Full-screen detail views - Summary: current level, daily intake vs. limit, time to sleep-safe - Timeline: 12-hour graph showing the last 4 hours of history and the next 8 hours of projected decay, with dose markers - Today's drinks: interactive log with edit-time and delete on each entry — fix a mis-tap or a forgot-to-log-promptly in seconds - History: 14-day bar chart with day-list drill-down (per-drink detail for recent days, daily totals going back 90 days) Personalize the model: Set your own caffeine half-life (3–10 hours). Smoking, genetics, pregnancy, and some medications all change how fast you clear caffeine, tune the decay to match you. Choose your look: Navy or Black background theme. Black is sharper on non-AMOLED (MIP) watches and easier on the battery on AMOLED displays. 12 drink presets included: Espresso, Americano, Drip Coffee (S/L), Latte, Green Tea, Black Tea, Red Bull, Monster, Cola, Dark Chocolate, Pre-Workout. Add, rename, and remove from the phone companion. Smart alerts - Warning at 80% of your daily limit - Alert when you hit your limit - Notification when caffeine drops low enough for sleep (within 2 hours of bedtime) Phone companion: Manage drink presets, adjust limits, view history, see weekly trends, and track your peak caffeine hours, all inside the Garmin Connect app. Watch-side edits and deletes sync automatically. Your data stays with you. Everything is stored on your watch and phone. No accounts, no cloud, no tracking. 100% free. No ads. No in-app purchases. Compatibility 42 watches across these families: - Vivoactive 4, 5, 6 - Venu 2, 2 Plus, 2s, 3, 3s · Venu Sq 2, 2m - Forerunner 165 (+ music), 255 (+ music, s, sm), 265, 265s, 955, 965 - Fenix 6, 6s, 6 Pro, 6x Pro, 7, 7s, 7x · Fenix 7 Pro family · Fenix 8 (43mm, 47mm, Solar 47mm/51mm, Pro 47mm) · Fenix E - Epix 2 · Epix 2 Pro (42mm, 47mm, 51mm)

v1.3.0 - Configurable caffeine half-life: tune the decay model to your own metabolism (3–10 hours; default 5.7). Settings → Caffeine half-life. - Background theme: choose Navy (default) or Black. Black looks sharper on non-AMOLED watches and saves battery on AMOLED. - Fixed a rare crash when opening the widget for the first time on the 1st of a month. -------------------- v1.2.0 Edit time and delete logged drinks: On the "Today's Drinks" screen, use UP/DOWN to pick a drink, then SELECT to open an action menu. - Edit time: adjust by preset offsets (-15 min through -3 hours, or +15/+30 min for fine-tuning). Useful when you forget to log a drink promptly. - Delete: remove a mis-tapped drink instantly. - Edits and deletes sync to the phone companion's History and Trends tabs. Note: on non-touch devices (fenix 7 family, fr955/965), UP/DOWN on the Today's Drinks screen now move the cursor instead of paging. BACK exits the widget. Same trade-off as v1.1.0's History view.