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📮 gckenny@gmail.comMewna uses Cole-Kripke (1992) actigraphy on iPhone motion data, plus your Apple Watch's heart rate, HRV, and sleep stages from HealthKit, to generate a sleep score and human-readable analysis each morning. Everything happens on your device.
No. The phone-only mode (place iPhone by your pillow) works on its own. Apple Watch makes the analysis more accurate by adding heart rate, HRV, and watchOS sleep stages.
Cole-Kripke shows ~89% agreement with PSG (polysomnography) in adults. With Apple Watch, accuracy further improves. That said, Mewna is not a medical device — for clinical concerns, consult a sleep doctor.
Mewna keeps the screen alive only during a tracking session. We recommend plugging in. iPhone-only mode uses ~10–15% overnight on iPhone 15 Pro on charger.
On the tracking screen, tap "Pause." Doing your thing, then tap "Resume" when you're back in bed. Pauses don't count toward sleep efficiency.
On your iPhone (SwiftData) and, if you're signed into iCloud, in your private CloudKit container. Mewna has no servers — your data never reaches us. See Privacy Policy.
Export: Settings → Export data (JSON). Delete: Settings → Erase all records. Both are reversible only by re-importing your JSON, so handle with care.
Yes. The Mewna Watch app starts a workout session and writes sleep + heart-rate data directly to HealthKit. The iPhone reads it on next sync.
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Email gckenny@gmail.com. Please include iOS version, device model, and steps to reproduce.