Along with the addition of the friends feature in Pokémon Go, a related feature - or even, a sub-element of that feature - was also added to the game. That feature is gifts, and this contributes to the dynamics of the friends feature. It also complicates things slightly further, but it's a small price to pay for making and nurturing friendly relations.
Sometimes, by spinning the Photo Disc of a PokéStop or Gym, a Gift may be received as an item. A Gift may only be opened by giving a friend the item; to do so, the "Send Gift" button on the profile of a friend may be used. The friend will then receive the Gift and be able to open it. Each gift contains a few items that are typically received from spinning a Photo Disc, and some may also contain a special Egg, provided there is space for the latter.
As with some other elements in Go, some restrictions apply. A Trainer will only be given a Gift as long as the Trainer has already sent some of the Gifts that have been collected. A Trainer can only send one Gift per day to a particular Trainer (but can send more to others) and must wait for that Trainer to open the Gift before sending another. Finally, a Trainer can only open 20 gifts a day, so prudence must be possessed in opening Gifts.
Whatever happens, the opening of Gifts counts as one engagement for the friendship level of two Trainers. It is possible for two Trainers to build up their levels simply by sending Gifts, and I've done it with at least one friend. Yet it would also be wise to consider who a Trainer has engaged with before sending another a Gift. It is also wise to consider where to get Gifts as well as whose Gift or Gifts need to be opened to make things as special as possible for both giver and recipient.
Gifts offer an efficient way for two Trainers to build up friendly relationships, but they must also be considered wisely. Still, there's nothing like a relationship that's boosted with a few instances of gift-giving, and the benefits are sufficiently attractive as well. In that sense, they are really the gifts that keep on giving.
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