Getting near objects. Django + Badoo
You keep track of all users, and you show all users whose coordinates are of a similar value.
Yes, that's a generic answer, but it is a very generic question.
I would not be surprised if there are modules for Django doing this already.
I have the following situation.
I keep track of a user's longitude and latitude using ios.
I send the longitude and latitude coordinates to a django server.
How can I use these longitude and latitude coordinates to determine what objects are near? 
Basically how can I use these coordinates to determine the list of other users near a user?