Back button on Android Phones

Question

A couple questions about the back button (as seen on the emulator)...

1. Do all Android phones have the back button as a hard, tactile button?

2. If s

Answer 1

For 3: Yes.

@Override 
public void onBackPressed() {
    super.onBackPressed();
    overridePendingTransition(R.anim.zoom_enter, R.anim.zoom_exit);
}