The Gesture Keyboard is a device that translates gestures into letters. It’s made by an Arduino Pro Micro, an HC-06 module for Bluetooth communication, and an MPU-6050 accelerometer.

There is an HC/06 Bluetooth module with an app to control the device from a phone, though while he’s posted some Arduino code there is no link to the app.

An Arduino mini pro provides the brains. A FT-232 USB to serial board is used to program the Arduino. A standard Bluetooth module has to have HID firmware installed.