I learned about Bolt from my airbnb host in Bratislava, my first stop on my last trip. I used Bolt in Bratislava, Budapest, Tallinn, Prague, St Petersburg ( I think) but not Moscow. Moscow had Yandex.Taxi. In France I used Blabla Car for longer distances where several passengers share the cost. I check what ride share a city has before I arrive. Hint : it's sometimes difficult to locate non-taxis at an airport so it's best to take the metro out of the airport. Didi is another one I used I think in Spain. I have used CityMapper in London for buses and trains. SayHi sounds fantastic.