MapSDK is fully functional mobile GIS, with map and navigation API. MapSDK is written in C++, initially for Windows/ Windows CE/ Mobile, then ported to Android. MapSDK still used in various products of big corporations around the World. If you use some Leica Geosystems devices with AutoCAD support, likely it has MapSDK inside. MapSDK license was sold to organizations/ companies in 32 countries Worldwide.
We released small part of MapSDK drawing engine as open-source at Github: xdraw
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