https://blog.sketchfab.com/inspect-models-and-textures-like-never-before/Last week they announced a new feature for their browser viewer, which lets you break down the assets into individual texture map views, lets you toggle between post-process and checker matcaps, and 2D views with UVs displayed.
Personally, up to now, I've always used Toolbag's viewer to present work. I've never updated to Toolbag 3 because I never felt the changes were too big for my stuff. Now with this turn of event, I don't think I'll ever do, at least not until they make some drastic updates. Sketchfab's free!