GeoDLL is a Geodetic Development Kit / Geodetic Function Library with worldwide 2D and 3D Coordinate Transformation, Datum Shift, Meridian Convergence and Extra Parameter with highest accuracy. Furthermore: Helmert and Molodensky Parameters, NTv2, HARN, INSPIRE, EPSG, Digital Elevation Model (DEM), distance and Time Zone calculations and much more. GeoDLL for geodetic and GIS development is available as 32Bit and 64Bit DLL and as C++ source code.