[Izkata]

I use an Android app called "Sleep", it just works by accelerometer with your phone on the corner of your bed. I've found it's not really good with its automatic rating and suggestions, but the activity graph has an extremely reliable wave pattern on the mornings I am well rested. Like an hour and a half of no movement at all, then an hour of restlessness, which repeats through the night. Usually the hour of restlessness even has the same pattern each time it happens. But any other pattern and I generally feel tired the whole morning.

Originally I got this app for its alarm, it tries to go off in the half hour before the alarm time when you're already partially awake. The sleep tracking was just a bonus.