During its panel at Comic Con, San Diego, Niantic Labs CEO, John Hanke, confirmed that a future update of Pokemon Go will allow the players to transform their PokeStops into Pokemon Centers.
Players will be able to heal their Pokemon in those Pokemon Centers, and also carry out some yet-to-be announced other actions.

During the Hall H presentation of Pokemon Go at SSDC, Hanke explained that Niantic is planning to encourage players to visit PokeStops by adding customization options to them.
Although he didn’t disclose what exactly those customization might be, he was clear that this would enable players to convert them into dedicated Pokemon centers offering several functionalities.

The easiest guess about these customization would be that it will allow players to use Pokestops as trading centers or Pokemon Breeding centers. However, we need to wait a bit more before more concrete details are revealed.
Earlier, Niantic mentioned that they prioritize adding the Pokemon training feature to Pokemon Go. Now, with this announcement, it seems like Niantic is going to add in both the features with one update.
This update might happen soon, but first they need to sort out the server issues plaguing the game.