So nice to see you sharing this. I think it's a very useful tool. I love your landing page, and the app is incredibly fast and intuitive.
When I was still working at Spotify, there were many cases where we needed to show a whiteboard in a meeting. It was always awkward, borderline impossible to show stuff in a mixed in-person/remote meeting. This is where I think your product will fit in. If it's remote-only, people can use an iPad; for in-person, the whiteboard will do the job. But these mixed scenarios - even just a meeting between two teams, one in London, one in NY for example - they were just unbelievably awkward.
The company looked into solutions like digital whiteboards, and while I'm sure they are great in theory, it also means you always need to get a room that has one of these. Anyone who's worked at a big corp knows how hard it can be to find a meeting room. We had some prototypes standing around (in open areas, actually - for whatever reason), but they were rarely used. These things are brutally expensive, too - your product is just an infinitely better idea IMO.
For my personal use (fully remote team), I found it tricky to hold the camera while also drawing. Using a tripod surely works, but then I can also just use the iPad and draw stuff there.
I would highly encourage you to promote this as a tool for larger corporations with multiple offices. The Zoom integration is fantastic in this regard - I don't know how hard it would be to also integrate with Google Meet (that was the software we used), but I think that that's the way to go.
Again, fantastic work. Very impressive implementation, and I think it's a great idea!
Disclosure to HN: Niko and I know each other personally, and I already used Grapic when it was in beta.