half-lyfe: Caffeine Coach

Energy when you need it. Plan your caffeine. Keep your bedtime in mind.

half-lyfe helps you log caffeine, preview your next drink and arrange an intended coffee around your day. Its ring shows estimated caffeine in your system and your chosen bedtime target.

PREVIEW YOUR NEXT DRINK
Pick a drink, portion and time. What-if compares your current estimate with the added drink and shows the projected amount at bedtime. A preview does not write to your drink history.

PLAN AROUND YOUR DAY
Choose your iPhone calendars or add times manually. Your Day brings your schedule, proposed drink and estimated finish-by time into one timeline. Google calendars appear when synced into Apple Calendar. Calendar access is optional. Planning runs on your device.

LOG EASILY
Tap the ring for your usual, or use Log drink to search the catalog. Supported widgets, Control Center, Shortcuts, Back Tap, Action Button and Apple Watch offer other ways to log.

KEEP A USEFUL HISTORY
Review your drink logs, tracking streak and self-reported drink effects. Optional Apple Health sleep observations add context for comparing caffeine and sleep. These comparisons do not establish that caffeine caused a sleep change.

GET TIMELY REMINDERS
Choose planned coffee, finish-by and other reminders. Notifications are optional and editable in Profile. Approving a plan never logs a drink automatically.

half-lyfe Pro is an auto-renewing subscription for the currently available tracking, previews, local planning and history features. Eligible yearly subscriptions offer a two-week free trial; a monthly plan is also available. Your local billed price, period, trial eligibility and renewal terms appear before purchase. Payment is charged to your Apple Account. Manage or cancel in Settings > Apple Account > Subscriptions. Restore Purchases restores access, not device-local drink history.

AI planning is not available in this release or sold as an active subscription feature. Groups and iCloud tracking sync are also unavailable.

Terms of Use: https://kadenpriebe.github.io/halflife-site/terms.html
Privacy Policy: https://kadenpriebe.github.io/halflife-site/privacy.html

Caffeine amounts, finish-by times and bedtime projections are estimates, not measurements or guarantees of sleep or performance. General wellness only, not medical advice. Ages 13-17 have lower intake limits and no energy-drink recommendations; these limits are not an endorsement of teen caffeine use.