Paid iPad app: http://itunes.apple.com/us/app/garageband/id408709785?mt=8&uo=4&at=10l6SU
Free iPhone app: http://itunes.apple.com/us/app/garageband/id408709785?mt=8&uo=4&at=10l6SU
Paid iPhone app: http://itunes.apple.com/us/app/garageband/id408709785?mt=8&uo=4&at=10l6SU
Paid Mac program: http://itunes.apple.com/us/app/garageband/id408980954?mt=12&uo=4&at=10l6SU