Nadir Izrael and Misha Seltzer are demonstrating IOIO OTG connected to a Nexus 7 acting as a device (getting power from the tablet)
This code will be soon submitted into the main IOIO repository, but if you absolutely can't wait for it, and don't mind using unreviewed and possibly buggy code, you can find it here:
https://github.com/mishas/ioio/tree/d...