Before using you need to set up an account and you need a local phone number. Once you log in you can set your departure location (the internal GPS isn’t very accurate so be careful) and your destination (seems easier to set it on the map, the destination box doesn’t recognize numbers) then you will get an approximate price. That’s as far as I’ve gone so far, don’t need a taxi yet but wanted to set it up and test before I actually need it. this app was written by the same guy who wrote the Voy En Taxi app which doesn’t work as well (see my review).