The battle for the hearts and minds of geo developers creating map-based apps is on. Last month, Twitter turned on its geo API, and services like SimpleGeo and the GeoAPI are offering to do a lot of the heavy lifting for startups that want to create cool geo apps. Not to sit on the sidelines, Google just tweaked its Google Maps API so that it now supports spatial search and search feeds.

Spatial search allows developers to search an area of map for particular features. Their apps would call these searches through a search feed, which can search a boxed area or within the radius of a certain lat/long point. Geo search results can be sorted by different attributes such as distance. Plug this spatial search into Google’s growing directory of local businesses and a developer perhaps could use the API to build an app which shows restaurants or shoe stores within a boundary on a map.

Being able to ask for all the interesting places within a 10 block radius or within a county opens up all sorts of possibilities. Creating geo apps is getting easier and easier with all of these geo platforms springing up. And of course there is nothing stopping developers from mixing and matching different layers of geo data from different APIs.

Update 11/17: You can find out more info at the Google Geo Developers blog, which just put up a post on the subject.

(Hat tip to Bob Hitching at Geome.me)