The game reflects a high quality product as we've come to expect from Gameloft and includes 17 real songs including Beat It, In the Shadow, Girlfriend, Message in a Bottle, and Rock You like a Hurricane. All songs can be played on guitar or drums.
The gameplay video shows guitar portion only and tutorials for both sections:
App Store Link: Guitar Rock Tour, $9.99
Note: This game does not presently work on the iPod Touch.