First I should point out that I have never used garage band on any other platform, so if you are looking for a review that will give you a clue as to how much of the usual garage band functionality you can expect then, well, keep looking.
I chose Garage band for iPad because I needed to knock up a rough demo of a tune I was writing, and the musician I was witing it for was not so confident with his sight reading that he could read it off the page at a recording session. He is a great jazz musician though, so I knew that if he just heard the melody and had a rough idea of the harmony we would be away.
To my surprise Garage Band for iPad turns out to be a great notepad tool for composition. There are a number of different sounds supplied with the basic download, and you can record tracks by playing on a virtual keyboard, or a virtual fretboard. There’s even a fret-less bass fretboard for jazzier bass lines. The virtual keyboard even has touch sensitivity. There are also ‘intelligent’ instruments that improvise (very well) in a number of different styles according to the criterion the user specifies. You can also record via in built or plug in mics.
The one thing I couldn’t find that would have been useful was the ability to export as music score.
http://www.apple.com/ipad/from-the-app-store/apps-by-apple/garageband.html
