Ive actually used this app for several years now and it has continued to hold its position right on my main screen of apps. What we really get a kick out of is the song book. Imagine guitar hero but for a trombone. The app tells you where you should be tapping and when to play a song. This is a riot when you get a group together and everyone tries to keep up with one of the faster and more difficult songs! This app is what it would look like if Apple themselves added a trombone to garage band. It has that level of polish.