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 need to build your own light or motor interface to the parallel ports binary outputs. For more details, please visit http://terakuhn.weebly.com/phone_usb_controller.html.
This app can also be used to determine if your Android device has USB-OTG hardware support. If you plug a USB-OTG adapter and a USB device into your Android device, this app can tell you if your device recognizes the USB device and will act as a USB host. If it doesn't, then your Android device doesn't have USB-OTG hardware support.