Codes in-game provide a range of freebies, from special Pokeballs to clothing and accessories. However, they can only be used once, as stated on the Niantic website: “Niantic offers a limited ...

This is also simple to do. In Map View, you need to tap the Pokeball button. From there, you can tap the shop button and at the bottom of the screen, there is a text field where you can enter it and ...