"Most location databases (such as PostgreSQL and Mongo) let you query based on all points within a certain radius, but any features requiring more advanced quer

"Most location databases (such as PostgreSQL and Mongo) let you query based on all points within a certain radius, but any features requiring more advanced querying are hard to come by. For example, I don't know of any freely available database where you can provide an arbitrary polygon of geographical coordinates and it will return the points within that polygon." PostGIS (an extension for PostgreSQL) does this really well. The most notable thing about SimpleGeo (to me) was that they were able to build PostGIS-like features on top of Cassandra. That's certainly attractive from a scalability perspective. I was really excited to try SimpleGeo out, but decided it was just easier--and less risky since I don't have much NoSQL experience--to use PostGIS. It also wasn't clear to me whether you could store NON-geographic data in SimpleGeo (such as user accounts). A (very) brief look at their docs seemed to suggest you couldn't, and using multiple datastores seemed messy to me...