Most Android devices have multiple sensors like light, gravity, proximity, etc.
Just try it up to control your music playback in a cool new way.
You require to raise your phone to the ear, and it should be answered the calls.

Apart from that, there is a huge list of other call-related gestures.
This app carries with you; look at these now.
Lock and Unlock your gear by using the gestures like waving a hand over the proximity etc.

You would get all those gestures running.
Make your gesture for any action or opening of the app, anything.
For Camera/Flash
1.

This is sometimes inaccurate, but you will find great results if you work with it.
Calculate the Distance from the objects using the Smart Distance app.
Using the old Android rig could be no better than this.

Just use your Old Android camera as the surveillance or the motion detector by installing the Motion detector App.
For Magnetometer
1.
Accelerometer: Just use the Android unit to check or measure up the devices speed or acceleration!

For Gyroscope
- you oughta calibrate it first; then, you’re free to perform the designated action.
I hope you like the method, dont forget to share your views!
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