This app was mentioned in 3 comments, with an average of 1.00 upvote
Music hero is probably the best one I have played, I installed in all of my Android phones so far and had spent hours every time, it's a perfect time killer, the only problem is that it works with songs you have in your phone (includes three songs of its own). It's a guitar hero like game. My favorite song for this game is "bodies" from "the drowning pool".
Not that I know of, but Music Hero works offline. It's pretty bare bones, but it's the same genre.