Likewise. I've bought a couple of watch apps which are supposedly automatic. Sleepwatch seems to work well but concentrates more on time in bed (whether awake or asleep dont matter) but does offer the option to edit times and add sleeps if you forget. The display of results shows a really big graph of time in bed, and a really tiny one of the quality of sleep and its worse than useless for me.
The best sleep tracker I have ever had (and which requires a routine to get it going) is Sleep Cycle. They don't have a watch app yet but apparently are working on it. Here's a screenie.
Cant even remember the name of the other one. It was hopeless, didnt even register sleep or being in bed at all.
I'm still using Sleep++ though (when I remember) and a general alarm if I want to wake at a particular time.