Just posting a short video to show the gear I use to get both cabled audio and midi from my iPad to my Akai MPC Live II.
HyperDrive HD319 – I linked to the Hyper Drive site, but this is around $80-$90. Personally I shopped around and was able to get it with discounts/sales at Best Buy a year ago for $60. It does give you a lot of features though, so definitely worth checking out if it is compatible with your iPad.
Roland UM-ONE – This is the USB Midi interface I used for the USB to Midi conversion. Nothing special about it, but it does work as a generic USB device, making it compatible with the iPad.
Hope this helps you out!