Just thought I would make a post on here about this awesome game.
Cytus is a music game much in the vein of DJMax Technika. It's got a range of Dance, J-Pop, Trance and Drum and Bass at the moment with 3 'Chapters' of the story available.
It's free to download with a few restrictions (Which I think limit you to the 9 tracks in Chapter 1, but I bought the game so damn fast I wouldn't know much more than that!), but so far it's a blast to play. RayArk, the developers have got a somewhat novel approach to music game 'DLC' too... for every 10,000 purchases of the full game, they'll release a new chapter of 9-10 songs until the full 10 chapters have been released at no extra cost to those who have upgraded to the full version.
It's available on iOS (iPhone, iPod Touch and iPad) & Android. My only concern is make sure your device can handle multi-touch as there's a hell of a lot of that in there!!
You should be able to find Cytus on the iTunes Store and Google Play.
The official website is here :-
http://www.rayark.com/g/cytus