I am going to ask that one question that perhaps has been already asked a million times.
I am making an app for iPad and want to give users the ability to multi-sel
I use ALAssetsLibrary and rolled my own UI. The problem with UIImagePickerController is that it says you are supposed to dismiss the view controller in the didFinishPickingMediaWithInfo callback, so hacking multiple selection by not dismissing may run into problems. I know I did when I first tried it. I can't recall exactly what went wrong, but there were cases where UIImagePickerController simply stopped working if I didn't dismiss it like the docs say.