Here at Happy Vampire Software, we develop apps for android phones and windows 7 phones.
So Far we have programmed and deployed one app to the Android Market. Tune Pop, with over 25,000 downloads it has been a great success. Also we're working on many other useful apps that will be launching soon.
In the Windows Phone market place we have not yet released any apps, although we do have a few in mind. In fact a couple are being programmed now, hopefully to be release as soon as possible.