Say you’ve got an electronics project going full last and need to test it—what to do? Israeli tinkerer Ytai Ben-Tsvi worked his DIY magic to create the IOIO (pronounced yoyo). It’s a nimble slice of hardware that connects to an Android phone via USB.
According to the Make blog where Ytai’s IOIO was featured:
I’m very excited to announce the launch of a new product I’ve been working on for the past months! IOIO (pronounced: yo-yo) is a product which lets you connect electronic circuits to an Android device and control them from an Android application. It is comprised of a small (2.71.2? = 7x3cm) PCB that connects to an Android device with a USB cable and a software library (Java .jar file) that you use in your Android app which handles all communications with the board.
No firmware programming is required – only Android application authoring with a very simple API for controlling the pins on the board. No modification of the Android device is required – you avoid the complication of modification and the voiding of warranty.