This is a Free Version of Sleep Statistics app.
It is devoted to people, who would like to check their sleeping habits, would like to know more about how much do they sleep, see statistics, may be this app will change personal habits for the better, who knows? :)
Since its impossible to track when person starts sleeping and when finishes, I made it simple: when you are in bed you simply click "Im in Bed", when you woke up, when you getting up, - click "Im not in Bed". Since then, new record will be automatically recorded. If you have hard night, may be not able to sleep for a while, you can easily reset timer or modify your data later: just simply open calendar, find your record and modify it. If you forget to track your night, - you can easily insert new record next day too. After some time, you will be able to see how much time do you spend in bed (how much do you sleep), when you get up and when you go to bed.
Additionaly, since this application is a Clock App too, you can set up Alarms for a week, I believe it could be a nice addition to Clock application from Apple. It has couple limitations though: alarm will not ring in "Do not Disturb" or in Silent modes if application is not active. Please, set Alarm at least 1 min before the clock time for proper functioning.
Since alarm is a "notification" for iphone, I recommend to configure Notification as "Alert" message box. After that Sleep Statistics alarms will work even when application is not active.