You have two options that I've found. One of them is called Band and the other is Beatmaker. Here is a video for beatmaker., the application goes for 20 dollars in the AppStore. My suggestion to you is to purchase the cheaper one: Band, which has less features, but is still a nice application to fool around with. (It was featured by apple) That way you can get a good feel for how it works then see if you want to drop the cash on a bigger one later. Band goes for 3.99.
Post edited at 8:29 am on Nov. 16, 2009 by wOlF
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I don't know, I think I am 70/40 on this issue. I always give it my 110%.