half-lyfe: Caffeine Coach
Know your caffeine cutoff
Free · In‑App Purchases · Designed for iPhone. Not verified for macOS.
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. Local planning runs on your device. Optional AI planning ranks generic time windows after a separate opt-in; on-device checks govern every suggestion.
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.
Optional coffee-stop planning helps you choose a café and preview walking time. Connect a compatible external agent to share future intended plans and receive drafts for review in half-lyfe. Agent accounts and custom-connector availability depend on the provider. Suggestions never log a consumed drink automatically. Groups and iCloud tracking sync remain 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.
Ratings & Reviews
A fresh look for your everyday caffeine check-ins:
• Redesigned Apple Watch screens with a clearer caffeine ring and portion controls.
• Refreshed widgets and Live Activities that match the app.
• Updated guides for setting up quick logging.
• Optional analytics sharing, with controls to turn it off and request deletion in Profile.
Caffeine levels and timing remain estimates.
The developer, Kaden Priebe, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Linked to You
The following data may be collected and linked to your identity:
- Health & Fitness
- Purchases
- Location
- User Content
- Identifiers
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Seller
- Kaden Priebe
- Size
- 95.3 MB
- Category
- Health & Fitness
- Compatibility
Requires iOS 18.0 or later.
- iPhone
Requires iOS 18.0 or later. - Mac
Requires macOS 15.0 or later and a Mac with Apple M1 chip or later. - Apple Vision
Requires visionOS 2.0 or later. - Apple Watch
Requires watchOS 11.0 or later.
- iPhone
- Languages
English and 8 more
- English, French, German, Hindi, Japanese, Korean, Portuguese, Simplified Chinese, Spanish
- Age Rating
13+
- 13+
- This app is rated 13+ with content restrictions.
Some content may be rated higher, and may therefore be restricted and managed by the developer through in-app controls. - In-App Controls
Age Assurance
Infrequent
Alcohol, Tobacco, Drug Use or References
Contains
Health or Wellness Topics
- In-App Purchases
Yes
- half-lyfe Pro (Yearly offer) $19.99
- half-lyfe Pro (Monthly) $9.99
- half-lyfe Pro (Yearly) $29.99
- Copyright
- © 2026 Kaden Priebe