You know that feeling where you wake up from a nap groggier than you were before?
That groggy feeling, called “sleep inertia”, happens whenever you’re abruptly woken up from a deep sleep;1 the deeper you are in your sleep, the groggier you are when you’re woken up.2 This is why you wake up refreshed when you don’t set an alarm: your body has a chance to complete a full sleep cycle, so it wakes up naturally when you’re in a light sleep.
Enter the Power Nap app (available only for iPhone). Power Nap is made by the same folks who created Sleep Cycle; the powerful iPhone app that tracks your sleep phase and wakes you up when you’re in a light sleep. Power Nap also tracks your movements as you sleep through your iPhone’s accelerometer, and wakes you up when you’re in a light sleep phase of your nap, before you fall into a deep sleep.
The app has three modes:
- Power Nap: Up to a 20-minute nap. The app will wake you up within 20 minutes, before you fall into a deep sleep.
- Recovery Nap: Up to a 45-minute nap. The app will wake you up within 45 minutes, before you fall into a deep sleep.
- 1 Sleep Cycle: The app will wake you up after you complete one full sleep cycle. The average sleep cycle is about 90 minutes.
I use (and highly recommend) Sleep Cycle as an alarm clock–since I started using the app a few years ago, I haven’t woken up groggy once, not counting the times I only got a few hours of rest. Power Nap is the perfect companion app to Sleep Cycle. If you like to nap and own an iPhone, at $1.99 this app is a no-brainer, and there is no other app like it on the market today.
