Exactly as rumoured, Rock Band for the iPhone has now appeared in the App Store. EA made the app official shortly after the game was spotted in a mobile showreel for the company, and it's now available in the App Store for £6 or $10, depending on which side of the Atlantic you reside on.

 The game shares a lot of its mechanics with the Tap Tap Revenge series (which in turn took its cues from the console versions of Rock Band and Guitar Hero). You simply tap the screen in time with the music to play notes, and missing one will reset your score multiplier. Overdrive is present, as is the star ratings system from the console versions.

You can pick from guitar, bass, drums and vocals, though they're all performed by tapping the screen so there isn't much difference between them. You can't sing into the iPhone, unfortunately. Multiplayer is present - up to four players through Bluetooth, complete with Facebook Connect to make it more easy to rope your friends in.

There's 20 songs that come with the game, and more that you can buy from an in-game store. Here's the full tracklisting, which seems pretty similar to the Rock Band 2 tracklist:

"Attack" – 30 Seconds To Mars
"Girls Not Grey" – AFI
"Move Along" – All American Rejects
"Sabotage" – Beastie Boys
"All The Small Things" – Blink-182
"Hanging on the Telephone" – Blondie
"Learn To Fly" – Foo Fighters
"Everlong" – Foo Fighters
"Bad to The Bone" – George Thorogood & the Destroyers
"Hymn 43″ – Jethro Tull
"Bad Reputation" – Joan Jett
"Simple Man" – Lynard Skynard
"Ace of Spades ‘08″ – Motorhead
"Debaser" – Pixies
"Ladybug" – Presidents of The United States of America
"Give It All" – Rise Against
"Lazy Eye" – Silversun Pick Ups
"Cherub Rock" – Smashing Pumpkins
"Take The Money and Run" – Steve Miller Band
"We Got The Beat" – The Go Go's

If you pick it up on your handset, let us know what the experience is like in the comments below. Does the iPhone 3G have enough power to let the game run smoothly? We imagine it wouldn't be much fun if it were jerky...