Implement push notification service with a backend to add the message ios objective c app -- 3

I need that when someone its nearby to a X store it shows notification about that store, like promotions, marketing, discounts, etc. The backend (that have to be added to my backend that its done with codeigniter) will have a registration proccess (CRUD) of the enterprises with a list of message to send by push notification when someone its nearby to that specific store and with the ios app in hand, must be offcourse geolocalized