Nice stuff!.
I tried to use my galaxy tab 8.9. For the moment not a nice small OTG cable (now on order ), but a big USB/SD card adapter and an xbee.
Only rooted the galaxy, no need to install extra tools. I couldn't use the power output from the galaxy because the xbee seems to draw to much current.
Oh well, just a test but a great one.
Peter, great job on the GCS, now with this we can use all kind of communication directly to USB-Host supported android devices!.
Menno