As of June 2018, Pokémon GO implemented a new ffriend system. This friend system encompasses various different features, each will be detailed here.

Trades

After 2 years, trading finally enters Pokémon GO. However, you can only trade with players you're friends with and you need to be within 100 metres of the friend. When you do this, you can trade Pokémon at will. When you go into the trade system, you will see a range of CP for the Pokémon. This is due to the fact that when you trade a Pokémon, the IVs are completely rerolled. However, the higher your Friendship Level with the friend, the more likely you'll get high IVs

Trading is not a free thing, however. In order to trade, you will need to use Stardust. The requirements for stardust vary depending on Pokémon and their level.

Finally, when you complete a trade, you will gain a bonus candy of the Pokémon you sent, just as if you transferred it. If the Pokémon were caught further apart, you get more candy as well. This goes up to 3 Candy for trading over 100km. You can also achieve a medal by doing this

The Stardust Requirements are as follows

Pokémon Stardust Requirement
Good Great Ultra Best
Pokémon in both players' Pokédex 100 100 100 100
Legendary/Shiny Pokémon in both players' Pokédex 20,000 16,000 1,600 800
Pokémon not found in one player's Pokédex 20,000 16,000 1,600 800
Legendary/Shiny Pokémon not found in one both players' Pokédex 1,000,000 800,000 80,000 40,000
Special Trades

Special Trades are a type of trade that are only activated when you're trying to trade one of three things:

  • Legendary Pokémon
  • Shiny Pokémon
  • Pokémon not in one of the player's Pokédex
Due to this, you can only do one Special Trade a day. Due to the contents of the trades, it will cost a lot of Stardust to make the trade if you are not Best Friends

Certain events and seasons will increase the amount of Special Trades you can make a day as well. For example at the Pokémon World Championships you can frequently do over 5.