It’s generally accepted nowadays in Android that the exit dialog is an anti-pattern. Here’s a post from way back in 2012 making that case: https://www.androiddesignpatterns.com/2012/08/exit-application-dialogs-are-evil-dont.html. If the user presses back at the top of an app’s navigation stack, the expected behavior is to simply exit the app (i.e. finish the top activity).