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Pokemon GO Upgrade Items and Components A specific item can be used to develop certain Pokemon. The upgrade can be obtained by spinning a PokeStop's photo disc, and is often offered as a reward in Pokemon GO events. Upgrades can be used on armors, weapons trinkets, weapons, as well as gathering tools to boost their level. The upgrade costs Flightstones or crests based on the kind of item. Upgrade components Upgrade components can be inserted into trinkets, armors, weapons and gathering tools in o