Pokémon Go uses GPS to locate players and place Pokémon in the game world.
GPS, or the Global Positioning System, supplies location information from satellites and a compatible mobile device. Pokémon Go combines that location data with maps, mobile internet, and the phone’s sensors to create a location-based augmented-reality game.
Players move through real places to find Pokémon, visit PokéStops, and challenge Gyms. The game can use a phone’s camera to display Pokémon over a live view of the surrounding environment, but the camera is not what determines the player’s primary map location.
Bluetooth, NFC, and infrared are separate wireless technologies. Pokémon Go has supported accessories and nearby-device features, but those technologies do not replace GPS as the core system for tracking the player’s position on the game map.