Some of the ones I'm familiar with (in no particular order):
Are there others that I'm missing?
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Sign up to join this communitySome of the ones I'm familiar with (in no particular order):
Are there others that I'm missing?
Don't forget OpenStreetMap. There are many map viewers that can display the OSM data. I.e. JMapViewer, MapPanel and JXMapViewer for Java applications. At least the last one can also display Google Maps in your application.
ESRI (of course): http://www.esri.com/software/mapping_for_everyone/api/index.html
(Here's a blog post about the ESRI choices for the web: http://blogs.esri.com/Dev/blogs/arcgisserver/archive/2009/10/19/Which-ESRI-Web-mapping-API-should-I-choose_3F00_.aspx)
SimpleGeo (http://simplegeo.com)
UMapper (http://www.umapper.com)
CloudMade (http://www.cloudmade.com/)
There is also deCarta map services http://developer.decarta.com We are upgrading our devZone so please excuse the confusion for now. We also have J2ME and other mobile APIs < /propoganda>
[GIS Cloud][1] also let you embed maps just by copying and pasting the code snippet
[1]: http://www.giscloud.com/ GIS Cloud
nearmap.com - photo map resolution and a Timeline concept where you can see how things change over time.