First post so sorry if this subject has been raised before

Is it possible to manage incoming phone calls in DMD2, so that the whole of the screen is not taken over by the phone app. In other words on a complicated roundabout in a city I have never been in before, I would like to see the route in the map while negotiating the roundabout and not the phone app taking over the screen.
I guess I know the answer but it would be wonderful if it were possible.