Keyshot is described as 'KeyShot is an interactive raytracing and global illumination program developed by Luxion for both PC and Mac that breaks down the complexity of creating photographic images from 3D models' and is an app in the photos & graphics category. There are more than 25 alternatives to Keyshot for a variety of platforms, including Windows, Mac, Linux, Autodesk 3ds Max and Sketchup apps. The best Keyshot alternative is LuxCoreRender, which is both free and Open Source. Other great apps like Keyshot are MoonRay, Adobe Dimension, V-Ray and RenderMan.
GPU based, fast and easy to use