Rush is a quick-fire spin-off of Megacity, set in the same world. Travellers from invented outer states like Volska, Korvenia and Dravost head for Megacity's districts, and you have ninety seconds to process as many as you can.
There are five modes from day one: Rush, Daily Rush, Ranked, Shift and Practice. Leaderboards run through Google Play Games, so there's no account to make.