The game allows players to capture, battle, and train virtual creatures, called Pokémon, who appear on device screens as though in the real world. It makes use of GPS and the camera of compatible devices. The game is free-to-play, although it supports in-app purchases of additional gameplay items. An optional companion Bluetooth wearable device is planned for future release, the Pokémon Go Plus, and will alert users when Pokémon are nearby.