The app is already a huge success -- both in its official launch markets and beyond -- as trainers young and old try to build out their personal collections. It's a fun, if shallow (and slightly unreliable) game that encourages people to go outside and explore their surroundings. But be warned, as the app can lead you into a whole host of strange locations -- and crafty crooks have figured out how to use the game as bait for muggings. Unlike the regions of Kanto and Hoenn, Great Britain can be a dangerous place -- so stay safe and keep your wits about you.