Drones that take cell phones from one location to another.
pick up and drop off locations are independent and time relevant.
The can take long routes or short routes, as required.
The drones attach themselves to cars that have signed up for a service that pays them to allow drones to attach to their vehicles. The drones know the vehicles intended route, and optimize their travel based on this data.
Drones can attach themselves to airlines to travel across country. airlines have started making special areas of the plane where drones can attach.