That afternoon crash isn't random: it's your rhythm. Peaks analyzes your sleep to predict exactly when you'll focus, fade, and recover, so you stop fighting your body and start working with it. No manual tracking required, if you already track sleep, you're ready. WHY PEAKS WORKS Most sleep apps show you what happened. Peaks shows you what to do about it. Your energy rises and falls in predictable waves driven by two systems: your circadian rhythm (your 24-hour internal clock) and sleep pressure (how long you've been awake). Peaks models both using the two-process model of sleep regulation, the same science behind NASA's astronaut protocols. The result: a personalized energy curve that updates every morning based on your actual sleep. WHAT PEAKS TRACKS Energy Peaks – See exactly when focus is highest. Schedule deep work and important tasks during these windows. Energy Dips – Know when crashes are coming before they hit. Plan breaks and lighter tasks accordingly. Sleep Timing – Track when your body releases melatonin so you know when to dim lights and wind down. Sleep Debt – Every missed hour accumulates. See your running total and how it clears over time. Recovery Score – HRV and heart rate analysis shows how ready you are for today. Updated every morning. Vitals – Watch for unusual heart rate patterns that might indicate your body is fighting something off. Sleep Score – Five components of sleep quality: duration, timing, efficiency, consistency, and debt impact. BUILT FOR YOUR WORKFLOW Widgets for Home Screen, Lock Screen, and StandBy, your rhythm at a glance Apple Watch app with complications for energy predictions Calendar export overlays peaks and dips on your schedule Shortcuts integration for custom automations Smart notifications for peaks, dips, and wind-down timing CONNECTS TO YOUR DATA Works with Apple Watch, Apple HealthKit, Oura Ring, and Garmin. No manual logging, if your sleep is tracked, Peaks uses it automatically. YOUR DATA STAYS YOURS All calculations happen on-device. No accounts, no servers, no third parties. Your health data never leaves your iPhone. Join 100,000+ people planning around their biology. ~ Flo & Clemens from Vienna Peaks is a wellness tool, not intended for medical diagnosis or treatment.