Pokémon Sleep is a sleep-tracking spin-off Pokémon game for iOS and Android. It is developed by SELECT BUTTON inc., and is free to download with in-app purchases. It uses the player’s smart device or Pokémon GO Plus + peripheral to track and record their sleep data, which affects gameplay. The game features Snorlax as the central Pokémon, with other Pokémon appearing around Snorlax based on the player’s sleeping pattern.