Halvo: Caffeine & Sleep

Halvo helps you enjoy your coffee AND protect your sleep. Most caffeine apps just count milligrams. Halvo models the caffeine actually active in your body — using real pharmacology, not a rule of thumb — then predicts your level at bedtime and tells you your personal cut-off: the time after which the next cup starts costing you sleep. LOG IN SECONDS Add coffee, espresso, tea, energy drinks, soda, mate or your own pre-workout in a few taps. Halvo sums up the caffeine automatically and shows how much is still active right now. SEE YOUR CURVE Watch caffeine rise, peak and fade on a real concentration curve modeled with Bateman kinetics — and see exactly where you'll land when your head hits the pillow. YOUR PERSONAL CUT-OFF Everyone clears caffeine at a different speed. Halvo shows the latest you can have a cup without too much caffeine still active when you fall asleep. ON YOUR WRIST Halvo runs on Apple Watch too, with a complication for a glance-and-go check. A MODEL THAT LEARNS YOU — HONESTLY (PRO) With your permission, Halvo reads your sleep, heart rate and HRV from Apple Health to learn your personal caffeine half-life over time. Here's what makes it different: when the signal in your data is too weak to be sure, Halvo says so and uses the population value — instead of faking precision it doesn't have. WORKS WITH YOUR WEARABLES (PRO) Apple Watch, Oura, Whoop, Garmin — anything that syncs sleep and heart data to Apple Health. Halvo never connects to those services directly; it only reads what's already in Apple Health. PRIVATE BY DESIGN Your intake and health data are processed on your device. Halvo doesn't sell your data. FREE & PRO Halvo is free to track caffeine and find your cut-off. Halvo Pro adds the personal learning model, sleep insights and Bateman kinetics. Halvo Pro options: - Monthly — $3.99 - Yearly — $24.99 (with a 2-week free trial) - Lifetime — $34.99 one-time (no subscription) Payment is charged to your Apple Account. Subscriptions renew automatically unless canceled at least 24 hours before the end of the current period. Manage or cancel anytime in your Apple Account settings. Lifetime is a one-time purchase. Prices may vary by region. Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/ Privacy Policy: https://halvo.jnmcloud.de/privacy.html Halvo is not a medical device and does not diagnose, treat or prevent any condition. It helps you make more informed choices about caffeine.