Peaks - Circadian Rhythm Tracker

Overview

Peaks turns your health data into clear patterns so you can see what helps you sleep, recover, and stay consistent.

Scientific Foundation

Peaks uses the two-process model of sleep regulation, combining your circadian rhythm with sleep pressure to predict focus, fatigue, and recovery windows. It's the same framework used in aviation and shift-work research—the same science behind NASA's astronaut protocols.

Key Features

Energy Tracking

• 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 Analysis

• 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.

Apple Watch Integration

Seamless integration with Apple Watch, though Peaks doesn't exclusively require it. Any sleep data that syncs to Apple Health will work.

Privacy

Health data never leaves your iPhone. No sign-ups, no servers, no third parties. Peaks works entirely offline.

Pricing

• Free: Available on the App Store for devices running iOS 18 or watchOS 11 and later
• Peaks Pro: $4.99/month or $29.99/year - unlocks widgets, custom schedules, sleep scores, and calendar integration