[tomp]

It's not useful/a service; it's a way of ensuring order on the road. You can't (legally and safely) use mobile phones while driving; and when taxis stop on the side of the road, they should resume driving ASAP, not wait until they finish typing the destination.

Regarding "app" services, I agree, it's not necessary as they can map the path in advance, but they can't replace the existing "taxi" service (i.e. hailing taxi) that way (and I feel it's reasonable for cities to protect that service to a certain extent).