At last week's 3D GeoInfo conference, I learned about the open source Glob3 3D GIS and Glob3 Mobile 3D virtual globe.
There isn't much on the sourceforge website: "glob3 is an open source 3D GIS multiplatform framework written in java with a very non restrictive license and advanced features."
But you'll get more on this page for Glob3 Mobile: "Glob3 Mobile is an open source 3D multiplattform virtual globe engine, running in mobile devices (Android and Apple) and in HTML5 web browsers. In this first version, it allows to connect to any OGC WMS public layer, and show it on the globe. Glob3 Mobile is also a framework for virtual globe development. It allows to write plugins directly in Javascript, and these plugins can run in the three plattforms (Android / Apple / web browsers). The project is currently in development, but first plugin examples can be tested in this site."
The apps for iOS and Android are free.
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