Here is a bug report based on user feedback.
Drawing some nice cats on a whiteboard, it's cool, everything works as intended.
However, when trying to edit them from a smartphone, they don't appear in the whiteboard.
As suggested by the person reporting this, it could be useful to allow collapsing the toolbar. But I wonder if finding a way to move over the whiteboard wouldn't also be something to do.
Having a "hand" 🤚 button that allows to drag the document in every direction?