Niantic will be officially introducing Pokémon Go's multiplayer Buddy Adventure in early 2020. It will be coming to both Android and iOS. The feature will use the game's existing buddy system and AR+ mode so you can bring a more realistic version of your favourite Pokémon into the real world. The feature will also take advantage of the augmented reality platforms that Apple and Google offer. You will be able to interact with your Pokémon, feed it snacks to earn special perks, and help it grow. It's giving us Tamagotchi vibes. Each Pokémon will have a different quirk or way to express itself.
Soon you will also be able to use the Shared AR Experience mode, which is the multiplayer component. Two players will be able to exist in a shared AR world, allowing you to see your friend's buddy Pokémon and interact with it. You can even take pictures together. This feature will launch after the initial release of Buddy Adventure.
Source: The Verge