One of the greatest feature in iOS is to connect your MIDI keyboard to your iPhone/iPad or any other devices. Make sure that your MIDI keyboard support USB cable. Then you have to buy Lightning to USB Camera Adapter.
That’s it! Just connect USB cable with MIDI keyboard. Plug the USB to your “Lightning to USB Camera Adapter” and connect it to iPhone, iPad device.
If you MIDI keyboard doesn’t support USB then you can choose another approach to connect MIDI keyboard with iRig MIDI.