public static bool backButtonLeavesApp ;

説明

Should Back button quit the application?

Only usable on Android, Windows Phone or Windows Tablets.

By default this property is set to false, which means you're responsible for responding to Back button. You can do this by calling Input.GetKey and passing KeyCode.Escape.

If you set this property to true, clicking Back button:
* On Android will terminate the application.
* On Windows Phone or Table will suspend the application.