So i'm joining the iCraze in a few weeks again and picking myself up an iphone 4 (had an itouch 3g but i lost it a few months back) and i figured the internet connection on the go could potentially open up a world of potential for apps. I play piano/double bass/electric bass/guitar and i drum a bit as well and i figured there might be some good apps to compliment these instruments. I'm looking for things like synthesizers, good drum kits (I've seen VaDrum use DigiDrummer, anything better/worse?), tuners, chord books, MIDI keyboards, whatever. At the moment all i've got is: iRealbook Ultimate Guitar Shazam I think i might even purchase the iRig. Anyway, just wanted to see what you guys have been using?