Pokemon GO: Should you power Pokemon up before or after evolving?
In Pokemon GO, evolution and powering up are core mechanics intended to improve the combat capability of a Pokemon while also unlocking new Pokedex entries along the way. However, considering both are resource-driven, with powering up requiring Stardust and evolution typically needing a significant amount of candies, it may not be clear when to enact these mechanics for a given Pokemon.
Trainers may wonder if they should power up a Pokemon before evolving it or vice versa. When deciding this, it is usually more economical to evolve first, then power up the desired Pokemon in Pokemon GO.
Pokemon GO: Why evolving first is preferred
Although evolving a Pokemon or powering it up first won't dictate its full battle potential in Pokemon GO, there are a few reasons many trainers opt to evolve a Pokemon before powering it up.
After a Pokemon's evolution, they'll acquire new moves in many instances. If those moves are undesirable and players don't have TMs on hand to change them, it will cost a significant heap of Stardust to obtain a new move.
Moreover, in the long run, it costs less Stardust to evolve and then strategically power up Pokemon that are used in battles often. At times, players will power up a Pokemon significantly only to evolve them and find that they're not used all that often.
There are exceptions for particularly rare or powerful Pokemon, but the shifting meta of Pokemon GO can throw curveballs to trainers expecting to beef up and deploy certain Pokemon.
Stardust, in general, is more precious of a resource than Pokemon candies, especially at higher trainer levels where a large amount is required to power up Pokemon well into the high CP ranges.
This is amplified for Mythic and Legendary Pokemon, who need plenty of Stardust just to level at all. Candy can be accessed just by catching Pokemon and using Pinap Berries or the Buddy Pokemon System, providing some simple avenues compared to the work that usually goes into acquiring large amounts of Stardust.
Although, in the end, Pokemon GO players are free to power up or evolve Pokemon as they choose. They may find they have more Stardust available by being tactful in its use and only spending it on evolved Pokemon that genuinely have the potential to shine in battle.