How to review a web application code?

How should I structure the code for a Django web application to query a database based on location/map coordinates?

• Basically, like in google maps, the user enters in an address, or some data that pins down his location, and I want to bring up a map view with tags specific to that area. Eventually the use will  be quite heavy (etc 100-200 tags per zip code), so the code should be  efficient. More detail much appreciated. I'm using Leaflet, if that matters.

• Answer:

  As someone who worked for a software company that did a lot of work with geographical data, a good starting point is looking at GeoDjango (https://docs.djangoproject.com/en/dev/ref/contrib/gis/), a project specifically tailored for geographic information in Django, with support for geospatial querying — coupled with the PostGIS extension for Postgres (http://www.postgis.org/). However, be warned: you might need to brush up on some geography before diving into it.