Fanciful graphics include undersea settings, alien worlds, and metropolitan cityscapes.

It’s no coincidence that Phase was created by Harmonix, also the designer of mega-hit, Guitar Hero III. Similar to that game, Phase asks players to tap buttons in time to visual cues and songs’ rhythms. But instead of being locked into a preset list of tunes, Phase works with nearly any iPod song. This simple music game is catchier than the hook on a top-40 hit.

iTunes analyzes tracks on a Mac before transfer, chiseling out coherent pattern-matching targets that keep tempo with songs. Colored circles drift down the screen, sometimes mirroring Beck vocals, a Beirut glockenspiel, or a bass-line from any band. Players tap the middle row of three buttons in time to score points. And on occasion, the scroll wheel catches dots anywhere on-screen. It’s like Simon Says but requires immediate matching, not repetition.

In our tests, songs with a regular beat played by drums—or any instrument—worked best. We had to strain to find tracks that didn’t sync as well; solo-piano and guitar-and-vocalist songs were least coordinated.

The bottom line: Phase is constant, re-playable fun on nearly every song it encounters. It gives a rock-star hight without the late-night emergency room visits or morning regrets.

Company: MTV Games
Contact: www.phasegame.com
Price: $4.99
Requirements: iPod nano (3rd Generation), iPod Classic, or iPod (5th Generation)

Works well with nearly any iTunes song (MP3, AAC, Protected AAC). Includes seven songs to get started. Fantastic graphics, including fire-breathing unicorns. Simple, addictive rules.

Minor, rare iPod stutters interrupt flow.