One difference: I was casually browsing web pages on my phone, saw the link, and was able to try out the demo after 15 seconds of loading. Then when I was done

One difference: I was casually browsing web pages on my phone, saw the link, and was able to try out the demo after 15 seconds of loading. Then when I was done I closed the tab and that's the end of it. Nothing to install or uninstall, near-instant casual 3D interactivity (at least on a modern cell phone). I'd say that part is pretty cool.