arduino work as android controller ?

Hi, guys.

I want to add some physical buttons to an android system via arduino and I wonder if it is possible.

I just want some common functions like volume up and down, silent, back, home, menu, etc.

Any tutorial or reference is sincerely appreciated.

Thanks.

You first need to find and download the Android app that accepts the Arduino input

Why physical buttons, when you can command arduino via Wifi, wireless. The button can be on an android app.