Useless. Such a ripoff.

Seriously, I cannot believe I was duped in buying this app. 1) taxi numbers are out of date, 2) reviews are useless, 3) who cares if the taxi companys office or dispatch is close to my location. (Their screenshot of the map is misleading. They make it seem those are where the taxis are.) Charging $2 for this awful app is robbery. Good ol Google works just fine if you want to find a cab in the city. Plus there are other taxi apps out there that are either free or offer way more features.

I think the positive reviews are by the developers themselves.

The Smitten Kitten about Call a Taxi PRO - Instantly find a taxi-cab, anytime, anywhere., v4.2.5