Now I'll do some research to understand what's happening between the Android and the robot controller board:
Simple demo of IOIO with USB connection to phone
Relay control
Servo contro
The IOIO board has a "collection of libraries" and "libraries expose a set of Java interfaces". I have no idea what that means, but will jump in and see if I can figure out enough of this gobbly-gook to get the phone controlling a servo...