Is it possible to finish all activities in current Android task?
It was already asked here.
But basically there’s no such function… Maybe you could keep a collection of all the activities and finish them yourself, but I doubt that’s good practice.
Or if all your activities are in the same “stack” you could try the answer given by “user370305”.
There is another alternative. Whole application could be done using fragments with single activity. FragmentManager provide full control over fragments and it is possible to finish all of them.