The little IOIO is a board designed to work with Android devices. It is specially engineered to provide connectivity via USB or Bluetooth connection to any Android device.
Having an autonomous rover is awesome, sure, but it’s also a lot of work and many sensors since the robot should avoid obstacles and navigate to a target. The second option is to build a remote-controlled robot. The IOIO board was used in a rover with real-time camera capabilities and controlled wirelessly with an Android device.
For this robot, you need two Android devices: one for you and one attached to the rover. Also, you need a Bluetooth module, a robot chassis with motors and motor driver, and a battery for the electronics.
The price for this little board is $55.95, and you can purchase it from here.
This wheeled robot is easy to build and will help you understand how to robots controlled the robots wireless via Android devices.