Apple on Tuesday announced the release of GarageBand for iPhone and iPod touch.

Previously available for the iPad, GarageBand allows musicians to plug in their guitar to Apple’s devices and create songs on-the-go. The new version is a universal app, which means one app will work on all devices.

GarageBand also comes with some enhancements over the last version. You can now create custom chords for Smart Instruments; you can transpose songs in semitones or full octaves; the app has support for for 3/4 and 6/8 time signatures; you can reset song key without transposing original recordings; and the app has new audio export quality settings for AAC and AIFF (Uncompressed).

GarageBand runs on iPad, iPad 2, iPhone 3GS, iPhone 4, iPhone 4S and iPod touch (3rd & 4th generation). The app is available from the App Store for $4.99.