Oleg over at Circuits at Home has an Android ADK-Compatible Library up.  He gives us a rundown on the pitfalls of the ADK…

The ADK code is targeted for ADK hardware component, which is just Arduino Mega 2560 and USB Host Shield combined on a single PCB. However, they decided to move some pins around; as a result in order to use the code with standard “Arduino plus Shield” setup certain code modifications are necessary. One such modification has been posted on Romfont. I tried it and the code works well, however, this approach has issues. First, it creates yet another distro. Second, the code modification exercise would have to be repeated each time Google releases new version of ADK. Finally, it’s difficult to have both standard and Google USB libraries installed in Arduino IDE at the same time. Given all that, I decided to take different approach..

Check out his post for his solution.