Description

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 94 watches: - Vivoactive 4, 4S, 5, 6 - Venu 2, 2 Plus, 2s, 3, 3s · Venu 4 (41mm, 45mm) · Venu Sq 2, 2m - Forerunner 70, 165 (+ music), 170 (+ music), 245 (+ music), 255 (+ music, s, sm), 265, 265s, 570 (42mm, 47mm), 745, 945, 945 LTE, 955, 965, 970 - Fenix 6, 6s, 6 Pro, 6S Pro, 6x Pro, 7, 7s, 7x · Fenix 7 Pro family · Fenix 8 (43mm, 47mm, Solar 47mm/51mm, Pro 47mm) · Fenix 9 (43mm, 47mm) · Fenix 9 Pro (43mm, 47mm, 51mm, Solar 47mm/51mm) · Fenix E - Epix 2 · Epix 2 Pro (42mm, 47mm, 51mm) - Enduro 1, 3, 4 - Instinct 3 AMOLED (45mm, 50mm) · Instinct Crossover AMOLED - Approach S50, S70 (42mm, 47mm), S72 (43mm, 47mm) - Descent G2, Mk2, Mk2i, Mk2 S, Mk3 43mm, Mk3i (43mm, 51mm) - D2 Air X10, Mach 1, Mach 2, Mach 2 Pro - MARQ Adventurer, Athlete, Aviator, Captain, Commander, Driver, Expedition, Golfer · MARQ Gen 2 (all editions incl. Aviator)

What is new

v1.4.0 - Now in Finnish, Czech, German and French: on the watch, in the phone settings and on the companion page. The app follows your watch language. Czech, German and French are drafts; corrections are welcome on GitHub. - Touch: tap a drink in Today's Drinks, or a day or chart bar in History, to open it. Lists show arrows when there is more to scroll. - Day details scroll when a day has many drinks. - UP/DOWN now move the selection in Today's Drinks and History on button watches (Forerunner, Fenix and others), and page on to the next screen at either end of the list. - Fixed: days now start at local midnight. Before, drinks logged just after midnight could be missing from today's total and log. - Fixed: per-drink details are kept for 14 days, as promised. Before, they disappeared after about two days. - Long status lines now fit on small and round screens. -------------------- v1.3.1 - Now supports 94 watches (was 42). - New: Fenix 9 and Fenix 9 Pro (all sizes, incl. Solar), Forerunner 70, 170, 245, 570, 745, 945 and 970, Venu 4, Vivoactive 4S, Fenix 6S Pro, Enduro, Instinct 3 AMOLED, Approach S50/S70/S72, Descent, D2 and MARQ. - No other changes. -------------------- 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.

Screenshots

HalfLife Caffeine · Screenshot 0 HalfLife Caffeine · Screenshot 1 HalfLife Caffeine · Screenshot 2 HalfLife Caffeine · Screenshot 3 HalfLife Caffeine · Screenshot 4

Supported language (1)

English

Compatible devices (148)

Approach® S50 Approach® S70 (42mm) Approach® S70 (47mm) Approach® S72 - 43 mm Approach® S72 - 47 mm D2™ Air X10 D2™ Air X15 D2™ Mach 1 D2™ Mach 1 Pro D2™ Mach 2 D2™ Mach 2 Pro Descent™ G2 Descent™ MK2 Descent™ MK2 Descent™ Mk2S Descent™ Mk2S Descent™ MK3 - 43mm Descent™ MK3i - 51mm Enduro™ Enduro™ Enduro™ 2 Enduro™ 3 Enduro™ 4 epix™ (Gen 2) epix™ (Gen 2) epix™ Pro (42mm) epix™ Pro (47mm) epix™ Pro (51mm) fēnix® 6 fēnix® 6 fēnix® 6 Dual Power fēnix® 6 Pro fēnix® 6 Pro fēnix® 6 Pro Dual Power fēnix® 6 Pro Solar fēnix® 6 Solar fēnix® 6S fēnix® 6S fēnix® 6S Dual Power fēnix® 6S Pro fēnix® 6S Pro fēnix® 6S Pro Dual Power fēnix® 6S Pro Solar fēnix® 6S Solar fēnix® 6X Pro fēnix® 6X Pro fēnix® 7 fēnix® 7 fēnix® 7 Pro fēnix® 7 Pro – Solar Edition (No Wi-Fi®) fēnix® 7S fēnix® 7S fēnix® 7S Pro fēnix® 7X fēnix® 7X fēnix® 7X Pro fēnix® 7X Pro No Wi-Fi fēnix® 8 AMOLED (43mm) fēnix® 8 AMOLED (47mm/51mm) fēnix® 8 Pro fēnix® 8 Solar (47mm) fēnix® 8 Solar (51mm) fenix® 9 - 43 mm fenix® 9 – 47 mm fenix® 9 Pro - 43 mm fenix® 9 Pro - 47 mm fenix® 9 Pro - 51 mm fenix® 9 Pro - Solar 47 mm fenix® 9 Pro - Solar 51 mm fēnix® E ForeAthlete 245 ForeAthlete 245 Music ForeAthlete 745 Forerunner® 165 Forerunner® 165 Music Forerunner® 170 Forerunner® 170 Music Forerunner® 245 Forerunner® 245 Forerunner® 245 Music Forerunner® 245 Music Forerunner® 255 Forerunner® 255 Music Forerunner® 255S Forerunner® 255S Music Forerunner® 265 Forerunner® 265S Forerunner® 570 - 42mm Forerunner® 570 - 47mm Forerunner® 70 Forerunner® 70 Forerunner® 745 Forerunner® 945 Forerunner® 945 Forerunner® 945 LTE Forerunner® 955 Dual Power Forerunner® 965 Forerunner® 970 Instinct® 3 – 45 mm, AMOLED Instinct® 3 – 50 mm, AMOLED Instinct® Crossover AMOLED MARQ® (Gen 2) MARQ® Commander (Gen 2) – Carbon Edition MARQ™ Adventurer MARQ™ Adventurer MARQ™ Athlete MARQ™ Athlete MARQ™ Aviator MARQ™ Aviator MARQ™ Aviator (Gen 2) MARQ™ Captain MARQ™ Captain MARQ™ Commander MARQ™ Commander MARQ™ Driver MARQ™ Driver MARQ™ Expedition MARQ™ Expedition MARQ™ Golfer MARQ™ Golfer Mercedes-Benz Venu® 2 Mercedes-Benz Venu® 2 Mercedes-Benz Venu® 2S Mercedes-Benz Venu® 2S quatix® 6 quatix® 6X tactix® 7 tactix® 7 – AMOLED Edition tactix® 8 – 47 mm, AMOLED tactix® 8 – 51 mm, Solar Venu® 2 Venu® 2 Venu® 2 Plus Venu® 2 Plus Venu® 2S Venu® 2S Venu® 3 Venu® 3S Venu® 4 – 41 mm Venu® 4 – 45 mm Venu® Sq. 2 Venu® Sq. 2 Music vívoactive® 4 vívoactive® 4 vívoactive® 4S vívoactive® 4S vívoactive® 5 vívoactive® 6