Sleepy tracks your sleep cycles and store them in your Runkeeper account. You can choose to let Sleepy track sleep cycles automatically or you can enter them manually.
You can track the total slept time and additional parameters like REM time, Light deep slept time, time woken and many others.
Sleepy gives you a graphical overview of the tracked data for a better understanding of the changes in sleep cycles.
You need a Runkeeper account to use this app.If you don't have one you can subscribe directly trhough the app. This gives you access to the Runkeeper website and to an ecosystem of apps submitting data to it.