I spent a chunk of the weekend picking through the 1,500 plus iPhone games out currently, as I started pulling together a gift guide for the iPhone. As you can imagine it's quite a challenge to try and find a handful of gems among all of those games. Sure a bunch are shovelware, but there are also quite a few excellent titles. Take for instance Gameloft's Guitar Rock Tour. The GameLoft-developed title leans heavily on the Guitar Hero franchise for its gameplay mechanics and aesthetic, but it manages to do enough different to make it work on the iPhone that I found it to be quite a bit of fun to play. The game comes with two instruments to choose from and 17 songs, all of which I suspect are covers. To play through a game using the guitar you just tap your way through the notes on the four-fret guitar as they fall toward you down the neck of the virtual instrument. The songs drop sustained notes and lines of notes at you as well as a number of double notes. If you come across a line of notes you can slide your finger across them as they scroll down. Once you build up enough rock power you can activate the familiar power-up by sliding your finger up the gauge to go into a power-up mode that doubles your points.While some songs can be a tad difficult to follow along on the tiny screen, in general I found it to be quite a bit of fun to play. I wasn’t as taken with the game’s drums. The game has just two buttons for the drum mode. One on each side of the “musical highway” that drops down your iPhone. For some reason I had a lot more trouble keeping up with the song despite having half as many buttons to push as I did with the guitar. The drum mode also highlighted an issue both instruments have. The game tends to chug occasionally when you miss your notes. These occasional slowdowns can throw a wrench in your timing as you play through a song, leading to more chugs. Fortunately it didn’t happen so often that it broke the game. Guitar Rock Tour includes both a tour mode with unlockable achievements and a quickplay mode. What it doesn’t include, at least yet, is any form of multiplay or downloadable content. While the ten dollar game is certainly limited with its short set list and lack of multiplayer gaming, I still think this is one of my favorite games currently on the iPhone. I just hope that they plan to expand the title with more, free or cheap songs and perhaps another mode.