Updates for "Pokemon Go" are already rolled out on Android devices and iOS. The "Buddy System" is included in the new update which is a way for trainers to walk around while gathering more candies and experience.
According to iDigitalTimes, a Pokemon can be made a buddy by clicking on the trainer icon and a bar which is located on the bottom left should appear and has the option "buddy" on it. From the 'buddy' button, a player can choose the type of Pokemon to be a buddy.
If a "Pokemon Go" player wants to shift buddys, the same button can be used. A buddy will go with the player anywhere. It can sit or stand next to the person. It can even fly or simply sit on the shoulder. This all depends on what Pokemon has been chosen.
Each Pokemon has a different requirement of how many kilometers in order for it to get candies. This only means that each Pokemon is different from the other. However at this time there is no list yet of the Pokemon and its distance requirement.
In a report by International Business Times, if a "Pokemon Go" player assigns a Pikachu as the Buddy Pokemon, there will be a special surprise. Pikachu will hop on the shoulder of the trainer after walking a distance of 10 km.
Meanwhile, the Pokemon Go team is working on the Pokemon Go updates. They are trying to fix certain issues and also are trying to improve performance reliability. They are also trying to enhance the support for Pokemon Go Plus. Updates are slowly being rolled out for "Pokemon Go Buddy System."
So far with getting candies together with the Pokemon Buddy, there is no limit to the amount of it. A "Pokemon Buddy" cannot be stuck in the gym.