Ever thought "Hey I wish I could practice that totally awesome riff in my favorite song, if only I could find an MP3 player that counts down before the song actually plays so I have time to position my fingers..."
I did. And since no other developer seemed interested in tackling this obvious problem in the education of our future musicians, I did. Now you can jam with your favorite artists whenever wherever through your Android device. That is, as long as you have an MP3 of their songs.
(I strongly suggest you support your favorite artists by obtaining MP3 tracks legally.)