PowerNap: Nap Timer & Alarm
RUMAHSAKU CORP. Health & Fitness iPhoneiPadiPod touchApple Watch
PowerNap: Nap Timer & Alarm is a free Health & Fitness app for iPhone and iPad by RUMAHSAKU CORP. Requires iOS 17.0. Updated September 8, 2026.
- Price
- Free
- on the App Store
- Size
- 10 MB
- Age 4+
- Updated
- Sep 8
- 2026 · v1.0.4
Screenshots
About PowerNap: Nap Timer & Alarm
Your lunch break ends at a fixed time. So the real question isn't "how long should I nap" — it's "by when should I lie down?" PowerNap is a nap timer built around the watch on your wrist. It estimates sleep onset from heart rate and motion. It starts with a standard 15-minute suggestion. After 5 valid assessments, it uses your history to suggest a duration from 10 to 20 minutes and works backwards from your fixed wake-up time to tell you when to lie down. HOW IT WORKS 1. Set your wake-up time (e.g. 12:55) 2. Lie down by the suggested time and tap Start Nap on your watch 3. Heart rate + stillness estimate sleep onset — no tapping needed 4. Confirm whether you slept and rate grogginess, then rate return-to-work readiness about 30 minutes later After 5 assessed naps, history-based suggestions begin. MADE FOR YOUR WRIST - PowerNap estimates sleep onset from a sustained heart-rate drop and continuously observed stillness. Resting while awake can still resemble sleep. - Last night's sleep duration, resting heart rate and HRV shown as reference information - Backup notifications on both watch and iPhone - Without sufficient heart-rate data, no sleep estimate is made; the scheduled alarm still works. TRACK AND UNDERSTAND - Every nap recorded automatically: estimated onset and sleep duration, heart-rate curve - Wake-up and 30-minute assessments, weekly charts and start-time patterns - Insights based on your own answers and history - The heart-rate graph for your latest completed, non-cancelled nap is included without a purchase. Access moves to the next completed nap; older graphs require Pro. - Sleep totals and averages include estimates only when you confirm that you slept. No, unsure and unanswered records are excluded. POWERNAP PRO (ONE-TIME PURCHASE) A one-time Pro purchase unlocks history-based suggestions, older heart-rate graphs, history charts and insights. No subscription. With Pro, optionally wake before the scheduled alarm when the estimated sleep duration reaches your target. PRIVATE BY DESIGN Nap, heart-rate and assessment records are processed on your devices and are not sent to our servers. No ads, tracking or accounts. Purchases communicate with Apple through StoreKit. - Requires a watch running watchOS 10 or later - PowerNap is not a medical device and is not intended to diagnose or treat any condition. Sleep onset is estimated from heart rate and motion.
What’s new
Version 1.0.4 · Updated September 8, 2026
• Sleep-onset estimation now requires a sustained heart-rate drop as well as stillness. • Results and sleep-time totals reflect your answer about whether you slept. • View the heart-rate graph for your latest completed, non-cancelled nap without a purchase. • Improved Apple Watch readability and alarm reliability when sensor data is unavailable.
App privacy
The developer, RUMAHSAKU CORP., reported these privacy practices to Apple.
Data Not Collected
The developer does not collect any data from this app.
Alternatives to PowerNap: Nap Timer & Alarm
Looking for apps like PowerNap: Nap Timer & Alarm? Here are 6 similar apps on the App Store. The highest rated is Smart Nap: Power Nap Alarm (5.0/5), and all 6 are free to download.
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NapBest
2.0
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Smart Nap: Power Nap Alarm
5.0
-
NapSense
-
NapBoost
3.0
-
Ohirune - 昼寝タイマー
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Sleep Tracker & Smart Alarm
| App | Rating | Price | Last updated | Compare |
|---|---|---|---|---|
| PowerNap: Nap Timer & Alarm | – | Free | September 8, 2026 | |
| NapBest | 2.0 / 5 (4) | Free | Mar 20, 2026 | Compare |
| Smart Nap: Power Nap Alarm | 5.0 / 5 (1) | Free | Oct 9, 2026 | Compare |
| NapSense | – | Free | Oct 2, 2026 | Compare |
| NapBoost | 3.0 / 5 (2) | Free | Apr 22, 2026 | Compare |
| Ohirune - 昼寝タイマー | – | Free | Oct 3, 2026 | Compare |
| Sleep Tracker & Smart Alarm | – | Free | Aug 30, 2026 | Compare |