Pokemon trading with friends!
John Hanke mentioned in an interview that there will be more classic features like Pokemon trading with friends in the future.
In fact, Hanke says, Niantic almost didn’t include the Pokémon games’ key element of “evolving” a Pokémon into a new form to make it stronger, because they were afraid it might be too complicated for new players. But they eventually relented. And sooner rather than later, Hanke says, more classic features like Pokémon trading with friends is coming.