NETGEN is described as 'Automatic 3d tetrahedral mesh generator. It accepts input from constructive solid geometry (CSG) or boundary representation (BRep) from STL file format' and is an app. There are more than 10 alternatives to NETGEN for a variety of platforms, including Linux, Windows, Mac, BSD and Snapcraft apps. The best NETGEN alternative is Blender, which is both free and Open Source. Other great apps like NETGEN are Wings 3D, MagicaCSG, picoCAD and SALOME.
enGrid is an open-source mesh generation software with CFD applications in mind. enGrid uses an in-house development for surface meshing and prismatic boundary layers; a module for hex far-fields will be added in the next release.
