I experienced all those same issues. I don't really care about my sleep score as I'm just in it to abuse my body into giving me more coding hours. Autosuggesting tags is but a feature request and some developer attention away. As far as tagging data, I thought the whole point was so that you could keep your own metrics not that you had to. The only thing they can monitor is how well you slept. It's up to the users to correlate that with pre- and post- sleep variables. They have general comments about how to improve sleep scores, but it'd be nice if they offered suggestions based on apparent symptoms in your data.

The charger thing is super annoying, especially that they offered no avenue to recycle them instead of just chucking them in the garbage.

Now that we've got the monitoring down we're working on ways to help people improve their sleep. This blog post talks a bit about one of the features we're testing: http://blog.wakemate.com/2011/04/05/743/.

"It also isn't the best at preserving your data on Android, there have been a number of nights where I lost data due to bluetooth bugs, application crashes, accidentally running the device battery out, and so on."

Likewise, I gave up after a couple of weeks for the reasons mentioned in the article, especially re: saving my data on my Android/EVO. Perhaps some of the software updates have improved this, but mentally I'd already given up. It's an awesome idea. But once hardware is involved, the typical startup challenges seem to rise exponentially and WakeMate got more than their fair share.