From the outset, Guitar Hero doesn't deviate from the well worn path, featuring a setup familiar to those who have played Rock Band or Guitar Rock Tour. Notes fall down the screen in typical Guitar Hero fashion, while the player taps the "buttons" at the bottom when notes align. Fundamentally, it's nothing that hasn't been done before, but the implementation is what makes Guitar Hero stand out.
For a start, Guitar Hero works better than either Rock Band or Guitar Rock Tour do on the touch screen. In those prior games, I always felt the interface wasn't responsive enough, and it was very easy to miss notes or play the wrong ones due to how bunched together the interactive parts of the screen felt. While Guitar Hero looks no different from those other games, the interface feels much more responsive and efficient. Unlike Rock Band, where it was easy to mess up notes with a misplaced finger, Guitar Hero seems to clearly interpret the borders between its "buttons" and make sure that the area you want to tap is the area that works.
Guitar Hero spices things up a bit with a "strum" gimmick designed for the iPhone's touch screen. Simply put, it's a case of touching a note and then sliding to the left or right while keeping the finger held down. It's a very simple thing, but it does enough to change the way the game feels, especially when your fingers are slaloming across the iPhone during a particularly tricky solo. Star Power also makes its obligatory appearance, and its activation requires the pressing of a bar just above the note "buttons". The only problem with the Star Power is the fact that getting a breather between notes to activate it can be tricky, although it's far easier to use than Guitar Rock Tour's version, which stuck it far away from the notes.