It seems that a much requested item is finally coming to Pokémon GO.
One of the most-requested items in Pokémon GO history might be about to come to the game. According to The Pokemod Group, several things have appeared in the files that seem to indicate a way to improve IV's of Pokémon. This seems to indicate that we might finally be getting Bottle Caps in Pokémon GO.
Bottle Caps were first introduced in Generation VII, which included the Sun and Moon games. These have then appeared in all Pokémon games since. In the mainline games, you trade these items to someone, and they improve the IVs of one of your Pokémon.
These items have been requested to come to Pokémon GO for a long time. With the recent debut of the Lucky Trinket, it seems Niantic are open to introducing more powerful items into the game. It could be that a Bottle Cap is made avaliable through some sort of pass-system during GO Fest later this year.
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Data miners indicate Bottle Caps could be coming to Pokémon GO
The Pokemod Group has discovered several new lines of code that seem to point towards Bottle Caps coming soon.
Just the reveal of this code has triggered a wave of excitement from Pokémon GO Trainers. Everyone has a Pokémon that is just shy of that all important 100% IV hundo status, be that a powerful Legendary or a personal favourite Pokémon.

It seems like something is certainly planned, with options for a single or triple increase. A triple increase would mean a 14/14/14 Pokémon could become a hundo. This could be a temporary increase, hence the use of the word "bonus" but of course nothing is confirmed right now.
Like with the Lucky Trinket, more details should emerge over the coming months. Nothing appears in the code and doesn't somehow end up in the game. We don't know the exact details of a potential implementation but we do know something is on the way.
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