Trism was one of the launch games for the iPhone/ iPod Touch. While some of the other launch games only showed off one of the the device's features, Trism shows all of them off incredibly well.
In Trism, you are given a grid of triangles. Then, you use the touch screen to slide the rows and try to make matches of three or more. Then, you can twist the iPhone/ iPod Touch to make the the triangles fall in different directions, and help you build chains of matches. There are also two special triangles, one that makes you unable to slide that row, and another that will explode and end the game if you don't get rid of it. These gameplay mechanics translate into three game modes. in Infinism, you play until a bomb explodes. In Terminism, you play until you run out of time. In Syllogism, you are given some triangles, and you try to get rid of them all in using only a certain number of tilts. These modes are incredibly addictive and long lasting. The game also has achievements unlocked for doing tasks like making a long combo, or making the triangles in the shape of a heart, and online leader boards for more lasting appeal. THe games doesn't feature much sound, save for the the falling triangles, making matches, and clapping when you do well sounds. The games graphics are all colorful, and simple except for the designs on the triangles.
In conclusion, Trism is a great puzzle game. Perfect for puzzle fans, or iPhone/ iPod Touch owners.