How to exit an Android app programmatically?

Question

I am sure this question has been asked number of times because I read a few. My client wants me to put a button into his app where users can click and exit. I have read this

Answer 1

If you want to exit from your application, use this code inside your button pressed event:

public void onBackPressed() {
  moveTaskToBack(true);
  android.os.Process.killProcess(android.os.Process.myPid());
  System.exit(1);
}