New to the iTunes Store is Phase (iTunes link), an iPod rhythm game developed under MTV Networks. Closing mimicking the popular "Guitar Hero" console series, Phase lets users pick tracks from their music library, which are then converted into game sequences where players must match button presses and clickwheel motions to on-screen notes. Scrolling backgrounds include alien, urban and underwater settings. Two play modes are available: Quick Spin takes users through a single song, while Marathon strings together multiple songs, with increasingly hard notation.

Phase is a $5 download from iTunes, and is only compatible with iPod classics, third-generation Nanos, and fifth-generation standard iPods. It will not work with iPhones or iPod touches. The game also requires iTunes 7.5, released Monday afternoon.