PokéStop

PokéStops are locations in the real-world, often buildings or historical markers, that serve as refueling points for trainers.

Using a PokéStop
PokéStops display in blue and purple. When blue the PokéStop is available and can be selected by tapping the base of the PokéStop location indicator. To use, the trainer must be within the radius of the pulsating circle displayed coming from the indicator. If in range, the indicator will animate expanding to a pokéball icon. Once in range and the PokéStop is selected, the trainer can spin the inner circle with the picture of the PokéStop to receive items. After use, the PokéStop will turn purple for the trainer and will be unavailable for at least 5 minutes. PokéStop availability is per trainer and one train's use of the location doesn't prevent other trainers from using it.

Items Based on Trainer Level
PokéStops, when available can provide 3-7 items, selected randomly from those unlocked by the trainer. Items received can range from pokeballs, eggs, revives, and all sorts of other items. Other than leveling and buying them, it is the prime way to receive items.

Pokémon Lure Modules
Lure Modules are an item that can be attached to any PokéStop to lure more Pokemon to the area and last for 30 minutes once activated. Effects of Lure Modules apply to all nearby trainers in the range of the PokéStop and are limited to the area of PokéStop the module is attached to. When active pink leaf/heart particle will start displaying around the PokéStop to indicate there is a modue attached.

How stops are selected
PokéStops were pulled from Niantic's previous urban exploring game "Ingress" and are based on Ingress Portals. While at launch every PokéStop and Gym were based on Ingress Portals, not every Portal from Ingress was made into a PokéStop or Gym. The original Portals for Ingress were created by the players themselves. They were asked to submit Portals at locations that are significant landmarks, mostly cultural or artistic things. Niantic then reviewed these submissions and if they agreed that it was significant enough it became a Portal.

How to request a Pokéstop
At launch Niantic did for their previous game "Ingress", users are allowed to request landmarks to be made into PokéStop or Gym via an online form on their support site however Niantic is no longer accepting new requests. If the form is reactivated it can be found here: Submit location