Samsung Galaxy S4's Air Call Accept feature has become quite famous and interesting enough that there is an app available to enjoy the same on most Android devices.
The Air Call Accept/Reject function basically works with the help of the Proximity Sensor that detects proximity of an object or the user's hand and only then executes pre-defined command. There is a free app that allows the Android phone users to accept the incoming call with a simple wave gesture in front of the Proximity Sensor. Since the app has not been tested with large variety of devices, it may not work properly with select number of handsets.
Here is a simple guide to enable Air Call-Accept on your Android smartphone.
Download the Air Call-Accept free version from the Google Play store.
Launch the app by tapping on the icon.
By default the Slider option will be enabled. Switch it off if you don't want to use it.
After doing that, you will be able to accept calls by simply waving your palm on top of the proximity sensor area of the phone.
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