Destructoid - Harmonix's VidRhythm is a cool blend of musical exploration and remixing. It encourages you to be creative and silly. It makes you laugh at yourself. It's maybe more of an app than a game, but I'm sure you'll have fun with it, regardless of classification.
From the article: "Today at 5pm EST, Harmonix (HMX) had their 1st Annual Holiday Livestreamaganza for Child’s Play Charity. They had DLC code giveaways, horrible, vomit inducing Christmas sweaters, answers for questions, announcements for their games Rock Band (RB), Dance Central (DC), and VidRhythm, and fun times all around! Whats that? You couldn’t make it? Well thank goodness I’m here to fill you in!"
From the Review:
"Here are four apps for iOS that might tickle your fancy. The first is a game the uses the motion-detecting capabilities of the iPod Touch. The second is an app that allows you to create unique music videos. The last two are old-school vertical scrolling shooters that are a lot of fun."
"VidRhythm, Harmonix’s latest offering on iOS, is quite the oddity. Better known for their games Dance Central and Rock Band, their latest app, VidRhythm, is not a game at all. Games usually have te possibility of losing but this app only makes things that win."