In Japan they have the Go app that allows you to hail and pay for a taxi ride directly in the app. You pay all of the regular dates and fees. The app just adds an additional fee on top to pay for the service.

It was incredibly useful and easy to use. You could even see when the taxi accepted the ride, track their progress, and message the driver if there was a question.

I think ride sharing services are forbidden in Japan. But this app seems like the best of both worlds.