A power nap alarm for Galaxy Watch and Wear OS
Updated October 27, 2026 · Sources listed below
Your watch already knows your heart rate and whether you're moving. Power Napper uses that to do what a phone timer can't: start your nap countdown the moment you actually fall asleep, then wake you with a gentle vibration on your wrist.
How it works
- Pick a length: 10, 20 or 30 minutes with one tap, a custom length up to 8 hours, or Nap until a time (it fits the longest nap that still leaves you time to get ready).
- Lie back. For the first few minutes it learns your settled-in heart rate. When your wrist is still and your heart rate drops clearly below that baseline, it counts you as asleep.
- Wake up gently. Vibration builds over about a minute, with an optional alarm sound if you need it. Hold to dismiss or snooze, so a half-asleep swipe can't turn it off.
- Never oversleep. A backup alarm always rings, even if sleep is never detected.
Why a watch beats a phone for naps
- It counts real sleep. Research on nap length is about minutes asleep, not minutes lying down. See how long a power nap should be.
- It wakes only you. A wrist vibration works in an office, a car at a rest stop, or a shared room.
- It's already on you. One tap from a tile or a watch face complication starts a nap.
Compatible watches
Wear OS 5 or newer, including:
- Samsung Galaxy Watch 4 and every newer Galaxy Watch, including Classic and Ultra models
- Google Pixel Watch 2, 3 and 4
- OnePlus Watch 2 and 3, and other watches running Wear OS 5 or newer
It isn't available for Apple Watch, Fitbit (non-Wear OS) or Garmin.
Other features
- Nap history with a heart-rate graph for each nap, a weekly chart and streaks
- Rate how you feel, and it suggests your best nap length and time of day
- Rest stop alarm (loud right away, no snooze) for drivers and heavy sleepers
- Daily nap reminder, for example before a night shift
- Adjustable sleep-detection sensitivity and vibration strength
Price and privacy
Your first 3 naps are free with every feature. After that, a one-time $4.99 unlock: no subscription, no ads, no account. Heart rate and nap history are processed and stored only on your watch. Read the privacy policy.
Frequently asked questions
Is there a power nap app for Galaxy Watch?
Yes. Power Napper runs on Samsung Galaxy Watch 4 and newer (and other Wear OS 5+ watches). It detects when you fall asleep and wakes you after the nap length you chose.
Does the Galaxy Watch have a nap alarm built in?
The watch's alarm and timer start counting from when you set them. Power Napper is different: it starts counting when it detects you've actually fallen asleep, and always has a backup alarm.
Does Power Napper work without a phone?
Yes. It runs entirely on the watch. No phone app or account is needed.
How much does Power Napper cost?
The first 3 naps are free with every feature, then a one-time $4.99 unlock. No subscription and no ads.
Sources
- Brooks & Lack, Sleep (2006): which nap duration is most recuperative?
- Rosekind et al., NASA Technical Memorandum (1995): strategic naps in operational settings
- Hilditch & McHill, Nature and Science of Sleep (2019): sleep inertia, current insights
This guide is general information, not medical advice. Power Napper is not a medical device.