is it possible to do geospatial queries in appscale as outlined here: Geospatial Queries?
AppScale does not support the creation of geospatial indices at this time. It may be implemented at some point, but since it's still in alpha for Google Cloud Datastore, it may be some time unless there is a lot of demand for it or someone creates a pull request. I created a ticket for it if you'd like to track its progress.