Zero Brush - blendersensei.com/zero-brush Texture painting, sculpting, and baking addon for Blender.
Blender - Blender is the open source, cross platform suite of tools for 3D creation.
Sculptris - Sculptris: Enter a world of digital art without barriers.
Quixel Mixer - Mixer is a PBR creation suite that uses brushes and non-destructive layering to generate all types of maps.
Misfit Model 3D - Misfit Model 3D is a 3D model editor that basically operates with triangle-based models.
3D-Coat - 3D-Coat is the one application that has all the tools you need to take your 3D idea from a block of digital clay all the way to a production ready, fully textured organic or hard surface model.