For every body · in training

Train hard. Recover with proof.

Every morning, Kairos reads how your body actually recovered overnight and tells you whether today is the moment to push or to hold — then shows you the signals behind the call. Readiness, load, and sleep, on the Apple Watch you already train with.

Built for the work

Push when it counts. Hold when it matters.

Readiness, not guesswork

A morning verdict drawn from overnight recovery — HRV, resting heart rate, sleep, breathing — each measured against your own baseline, with the biggest mover named.

Load you can trust

Fitness against fatigue, and the form that emerges between them. See whether you're building, holding, or digging a hole — before the legs tell you.

The window, named

When the data lines up, Kairos tells you the window is open — and when to back off so the next hard day actually lands. No black box, no obedience.

No new hardware

The full picture on Series 8 and later.

Series 8 and later add wrist temperature to sharpen every morning's read. On an Apple Watch SE, you still get a complete, confident reading from four core signals. We tell you exactly what your watch can and can't measure — honesty is the brand.

Private, always

Your data is yours.

Your training and health data is never sent to us, and we can never read it. It stays on your devices and syncs only through your own private iCloud. No account to create.

καιρός

Know your moment.

Tomorrow morning, find out whether it's yours. Be first through the door.

Kairos is a general-wellness app, not a medical device. It does not diagnose, treat, or monitor any condition.