[Nursie]

>> Has any taxi service, in any city, rolled out a self-dispatching app for end-users?

Do you mean an app where an end-user can request a cab, or do you mean an app allowing you to become a cab?

If the former then there are at least two I know of in my small-ish south-coast city in the UK. And one in Perth, Australia.

If the latter, no idea.

[Nursie]

For the record that's West Quay Cars and Radio Taxis in Southampton, UK and Swan Taxis in Perth.

I'm pretty sure there are now companies selling OEM taxi apps to taxi firms, ready for deployment after some integration and rebranding.