This project is a sample for the new Bluetooth HID Device API, which was introduced in Android P. It implements a simple air mouse and cursor keys emulation on a Wear OS device.

Note: This is not an officially supported Google product.


This app is only compatible with Wear OS devices running Android P and above. You can use it to connect with pretty much any laptop or desktop computer, running Windows, Linux, Chrome OS, Mac OSX, Android TV, without any additional software, as long as it has a Bluetooth receiver.

How to use this app

  1. After launch, the first thing you see is the paired devices list.
    • You probably want to pair a laptop or a desktop computer if it is the first time you've launched the app.
  2. If you tap on "Available devices" option, you'll see nearby devices that you can try pairing with.
    • It's a good idea to try pairing with a laptop or a desktop computer.
    • At this screen, the Wear OS device is also discoverable for the nearby devices, so you can try searching for it on the other device as well.
  3. When you have a paired device, tapping on it will give you an option to connect to it. This will bring up the Input Mode dialog.
    • Sometimes this dialog pops up immediately after pairing, saving you a few taps.
  4. You can now choose between Mouse (the air mouse), Cursor Keys and Keyboard Input modes, and also can change a few settings.
    • Every mode (except for the keyboard input) has a welcome screen that describes the way to use it.

Navigating the source code

The main sections of the code tree are:

  1. /bluetooth
    • Everything related to the HID Device emulation, like report descriptor, app configuration, and everything else that uses the new Bluetooth HID Device API.
  2. /input
    • Handy utilities for sending actual input events, e.g. converting characters of an en-US keyboard to scan codes, or converting Rotation Vector sensor events to mouse pointer movements.
  3. /sensors
    • Implements orientation tracking using Google VR library. The GVR-based approach produces results that are a drop-in replacement for the Rotation Vector sensor, but doesn't rely on the watch manufacturer's implementation of that sensor.
  4. /ui
    • The user interface

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