Hi there,
That is a mandatory function (for the app to continue to function in the background), but that is not what we are talking about here.
We mean that when you turn the screen off (to save battery ... or because you just want to listen to the point-to-point directions by voice ... or whatever) that the app should not shut off. If you are navigating using Google Maps, for example, you can turn off the screen and put the phone in your pocket and still receive point-to-point directions by voice.) ... Make sense? Hope that clears things up.
G