There have been many attempts on making a decent Piano application for our beloved Windows Phones, but this one is truly my favorite. The application that was recently updated with features, and fixes to better it self is quickly becoming one of my most used applications. Being an owner of the HD2, I find the need for multi-touch based apps growing inside of me, and this is one of the very few that actually uses the multi-touch capability of the HD2, and soon, all Windows Phone.
The application loads fast, and brings up an 8 button keyboard, which you can change from 1-3 to bring up new levels. The application on my HD2 loads quickly, and the sound it produce is pretty decent, and using the multi-touch feature is quite pleasurable. Not to mention the awesome record, and playback feature, that is very easy to access by pressing the green or red buttons on the top.
If you are bored today, or want a theme song while you Watch Football(Soccer), this application should be top on your list.