Tired of playing Tetris, Bejeweled and Pac-Man on your iPhone? Check out Trism — a casual gem-style puzzle game that is highly addicted.

It’s similar in style to the popular Bejeweled game. Instead of shifting pieces up and down, you use the iPhone’s six-axis accelerometer to shift them more at an angle to incorporate the triangles. The objective is to match the sides of 3 pieces of the same color. When those pieces disappear the rows above slide down, no matter which way you have the iPhone or iPod Touch turned.

Whenever you rotate the phone, the triangles rearrange themselves depending on the direction of the rotation. Does it sound simple? This app has many game modes that will challenge you.

Trism is available at the iPhone App Store for $4.99. It is developed by Demiforce and was introduced as one of the applications released on the initial launch of the Apple App Store.

Demiforce currently has five games in development and will be launching two by Christmas. This includes a spin off to “Trism” called “Trismology.”

The Positives: Clear graphics, fun sounds, and challenging and engaging gameplay.

The Negatives: Like Tetris, it’s perhaps too addictive.

The Bottom Line: As one of the best puzzle games available on the Apple App store today. Trism does a great job in using the built-in accelerometer. Overall, it took three minutes to learn, but requires hundreds of hours to master. And at a price of $4.99, the game is a bargain.

Rated 4.5 out of 5 Stars.