If you want to connect a USB Sound Interface that draws too much power for your iPad heres how to do it.
When you plug in a USB device you might see the following error message:
The attached accessory uses too much power.
One relatively easy way around this is to use a powered USB hub to supply the juice to your interface. I’ve managed to connect a Behringer Xenyx 302USB Mixer using a generic USB hub plugged in. You still need the Apple Camera Connection Kit to connect the USB device. Being as I already had a 30pin Camera Connection Kit I’m also using a lightning to 30 pin adapter to get this going on iPad Air and Mini.
This solution means that you need to be near a power source but means that you do not need to ditch something that could work perfectly if teamed with a powered USB hub.
It should work for other USB devices that require more power than the iPad is able to deliver. I’ve only tried connecting the Behringer Xenyx 302USB Mixer to my iPad in this fashion, so I’ll be interested in hearing if you are doing something similar with different hardware.