You can now exchange Pokémon specific to Pokemon Go to evolve them. If you do this, you will save a considerable amount of candy, and you can improve your friendship with the other coach in the process.
The trading mechanism is quite simple. All you have to do is exchange the Pokémon that you want to change with another coach, then they send it back to give you their advanced new form. However, it does not work for all Pokémon. There is only one handle on which it works. Here is the list of Pokémon that you can change through trades:
If you have one of these Pokémon in your collection, contact another coach who you trust to exchange with them. You must be close to decent with them to trade.
This list is not the final. Ni antic developers will probably increase this list over time, and more Pokémon will arrive in the game. We can expect more Pokémon already in the game receive this because a handful of them in the original Pokemon Titles requires you to exchange them to evolve. We do not know when it will happen. Furthermore, we will update this list as we will learn about others, and we can expect it to become a new essential Pokémon Go.