The Arduino ADK is a combination of hardware and software designed to help people interested in designing accessories for Android based tablets & phones. On the flip side you could also using it to add a touch screen interface to your supporting hardware!
The Arduino ADK Mega board integrates a USB host controller and an Arduino Mega2560 making it Google ADK compatible! Open the doorway to new, exciting projects by combining the processing power and connectivity of your Android device with the physical computing versatility of Arduino! Interface with the outside world, display sensor data on your phone, control servo motors with your tablet, it's the ultimate experience in open source software/hardware interaction!
It's completely compatible with Android's Accessory Development Kit examples. For more information on using the board with the Android OS, see (Google's ADK documentation)
The Arduino ADK hardware is based on the Mega 2560. In summary, it has 54 digital input/output pins (of which 14 can be used as PWM outputs), 16 analog inputs, 4 UARTs (hardware serial ports), a 16 MHz crystal oscillator, a USB female B connector for programming, a USB female A connector for hosting Android devices, a power jack, 2 ICSP headers for ATmega8u2 & ATmega2560, and a reset button. For a full hardware overview please follow this link.
With this board you need to change the boards.txt file in your Arduino directory (find it in: Arduino-00xx->hardware->arduino) with this updated version that include also the Mega ADK board: boards.txt
Windows users in order to get working the board need a .inf file for this specific product: Arduino_ADK.zip For installation follow the same procedure on how install an UNO board on your computer or follow this pictorial guide if you are an WinXP user having a bit of trouble.