I have been using AutoSleep for a while now, and find the information it provides sometimes .... more than I need. Overall, I really like it and look at the app each day to see how I "did" last night.
It seems to work fairly well for the limited time I have used it; it will recognize middle of the night trips to the kitchen, etc and deduct those minutes from your actual sleep time. It will automatically start when it detects you are asleep so you don't have to necessarily activate it. It picks up on those unexpected mid afternoon naps when you doze off and didn't tell your watch you were going to sleep, and adds that to your daily sleep time. Overall, I find it useful, but YMMV.
It monitors heart rate, respiratory rate, "deep" sleep, "light" sleep, awake time lying in bed, sleep deficit, consistency in time going to bed, and waking and "morning readiness" - which I always get 1-2 stars (yep, higher is better).
I've always found the sleep tracking apps kind of a "black box". I mean, how can I verify I was in "deep sleep" at 2 am and "light sleep" at 4 am ... I can verify those 3 am munchie trips to the kitchen however, and for that, it doesn't lie.
