Tetris for the iPhone is a solid take on the classic puzzle game. It makes use of the iPhone's multi-touch screen to allow the user to control it. You drag your finger right or left to move the piece horizontally. Rotate clockwise by tapping the right side of the screen. Rotate counter-clockwise by tapping the left side. Dragging down and holding lets you do a slow drop, while flicking downward causes the piece to drop quickly. I was surprised by how well the controls worked out. I did have some trouble placing pieces accurately on some of the higher levels, but all in all the touchscreen controls are solid.
There are two game modes available, Marathon and Magic. Marathon is the standard "keep playing until the blocks reach the top of the screen" mode everyone is familiar with. "Magic" mode is 15 levels of progressively harder "challenges". On level 1, you must clear 5 lines. On level 2 it's 10 lines, etc. As you clear each level you can unlock special moves that take advantage of the touchscreen and accellerometer built into the iPhone. One of moves is to pinch the screen to make the currently falling piece change into a single block. The second move is bubble wrap. When activated all the pieces at the bottom of the screen turn into bubble wrap. You have a few seconds to pop them (by tapping the screen) to make openings on the board. The third allows you to draw on the screen to change the current falling piece to whatever you like. The fourth, wrecking balls, causes the current piece to turn into 4 irons balls that bounce around the screen as you tilt the iPhone back and forth. The final move, smash down, allows you to shake the iPhone downward to smash bricks of the bottom of the screen. If all these special moves sound gimmicky, it's because they are. They are kind of neat to mess around with, but in the end feel tacked on.
The graphics are bright and colorful. The music is upbeat techno-style. I didn't care for it much. You can't play music that you have on your iPhone while playing the game. This is very disappointing. I'm not sure if this is a problem with Tetris or a limitation of the iPhone.
There are no online play modes (or even a high score leaderboard type thing). This is very surprising, as the iPhone has built-in Wifi and EDGE/3g data capabilities.
At a price of $10, Tetris for the iPhone just doesn't have enough bang for the buck.