Used it at Dublin to get from the Hilton (charlemont) to my bus tour meet-up point in the northside of town at 6am-ish. Came in 2 minutes, lucky not much traffic that early (the construction from connecting the two tram lines jams up the streets during biz hrs) so got there early. I think most people used the Hailo app as there were several cab drivers waiting for people talking to the concierge. My phone was running out of space, so just stuck with the app I had.