DRONE: an open source Bluetooth controller for smartphones and tablets

“The controller works and functions just like a standard
six-button controller and uses Bluetooth to connect to your mobile
devices. What?s interesting about the DRONE is that it?s open to
customization ? users can upload their own code to modify the
characteristics of the controller. It?s designed to work with
emulators ? not regular touchscreen games, so it?s more for those
who are interested in retro gaming on their mobile devices, though
I?m pretty sure it?ll work with games that have been designed with
support for a physical controller (i.e. games for the Xperia
Play).”

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