Add a navigation Pause button. On a trip, if I decide to stop at a fast-food place, using a pause would stop provide directions, without canceling the trip.
Once unpaused, the navigation would resume with corrections to continue the trip from the unpaused location.
In this example, it would keep navigation from telling you directions while you are trying to order in the drive-thru line.
To start your “Pause” press Cancel. To resume, select Navigation and pick the last destination from the top of the history list.