Currently I developed this for desktop browser, so it might not work well on mobile. But I will improve and update it.

You should be able to do pinch zoom support for laptops with a trackpad, too. I think it would be

window.addEventListener('wheel', ... )

Fantastic work!

Ok, I'm on desktop now. And I notice another "issue". When I use my mouse wheel to zoom, the point that my mouse cursor is on is not stationary. This makes it hard to zoom in on e.g. a specific aircraft or landmark.