Night and rotating shifts scramble your body clock. ShiftRhythm estimates it from your roster and Apple Watch — and gives you one daily card: when to seek or avoid light, when to nap, and how recovered you are.
Download on the App StoreSee your estimated melatonin onset (DLMO) and biological night (CBTmin) at a glance — with a sleep score.
When to seek bright light to advance your clock, and when to stay dim so you don't delay it.
Timed to your circadian rhythm — including a dose strategy for caffeine.
Last night's sleep plus HRV and resting heart rate — should you push today, or recover?
Panama 2-2-3 (day/night), Pitman, DuPont, Fire 48/96, 12-hour rotations — plus Korean and Japanese patterns, or build your own.
Everything is computed on your iPhone. Your health data never leaves the device — no servers, no account, no ads. The science behind every estimate is documented inside the app.
※ ShiftRhythm is for general wellness and reference only. It is not a medical device or a diagnostic tool.