Geohashing Algorithm
We can use user's longitude and latitude to determine the point of interest (POIs) around the user. Here are the steps:
Get the users' long/lat
Compute it's geohash
Determine what prefix you want to use: The longer the prefix, the closer together the points
Match prefix with geohashes of POIs
Optimize count of POIs
Reduce # of prefix match if you want more points
Increase # of prefix match if you want less points