Turn your smartphone into a microcontroller. The USBController app is for controlling hobby lights or motors through an Android device's USB-OTG (On The Go) port. This app allows you to set (turn on) or clear (turn off) up to eight signals (Data D0 through D7). To use this app, you need to plug together your own harness from an Android device with USB-OTG hardware support to a IEEE-1284 parallel printer port. You do not need a separate Arduino controller as other apps require. After that you ne