SketchUp is described as 'Versatile 3D modeling software for architecture, engineering, film, and gaming. Offers tools for both professionals and hobbyists available in free and paid versions' and is a leading 3D Modeler in the photos & graphics category. There are more than 100 alternatives to SketchUp for a variety of platforms, including Windows, Mac, Web-based, Linux and iPad apps. The best SketchUp alternative is Blender, which is both free and Open Source. Other great apps like SketchUp are Sweet Home 3D, FreeCAD, Autodesk AutoCAD and Shapr3D.