I feel the need to add this: If anything refers to hacking something that ISN'T an Apple product as a "Jailbreak", then it's most likely fake, and you should run.
That's from my experience, anyways. Please correct me if I am wrong.
@Xdqwerty, Osu! Tatakae! Ouendan! is the Japanese version of the game, different settings/characters/songs but otherwise identical mechanics. I played that before I knew about Elite Beat Agents lol. Both fantastic games https://en.wikipedia.org/wiki/Osu!_Tatakae!_Ouendan