Blender - Blender is the open source, cross platform suite of tools for 3D creation.
Putty3D - SCULPT ANYTIME, ANYWHERE
Sculptris - Sculptris: Enter a world of digital art without barriers.
Sketchfab - Sketchfab is an industrial design software tool is useful for ideation and for beginners in the industrial design field.
forger - forger is a digital sculpting application for the artist who wants to be able to sculpt anywhere.
ShapeShop - ShapeShop is an advanced and professional 3D design and modeling application that comes with an easy-to-use and user-friendly interface.