May I suggest PlaceLogic?
We have two APIs specifically designed to meet the needs of SimpleGeo
customers. PlaceLogic Simple Migration API lets SimpleGeo subscribers
switch with minimal effort and cost by emulating SimpleGeo's API
endpoints and responses. And our PlaceLogic Advanced API is for
customers who can modify their apps and want additional location-based
analysis and processing features.
Learn more here:
http://placelogic.com/g/simplegeo/index.php?kw=11