dayze

https://www.fovotec.com/architectural has an animation, and it looks pretty great - somehow feels more like actually 'walking' into that space.

Sukhbir Singh just commented: Thank you everyone for the comments and suggestions. I just wanted to share that we have identified the app and will update this task tomorrow. (And yes, it is a mobile app.)

I think it must be happening on your end. When I search for the same thing I get normal images and none of the domains you list above.

What are some more complete alternatives?

I think there is a blurred line between "lightweight" and "complete", and the various frameworks land either side of it.