Useless
The app doesn’t work at all, at least for Menorca. Try any route (if you manage to find your pick-up and arrival locations), you’ll get a message displaying a number you need to call (without the prefix for Spain of course, it would be too easy), except that the Minorcan taxi website will tell you they don’t take any reservations by phone (oh, and you can’t do it through their website either). Good luck!