I do chalkboard-style, or whiteboard, diagrams with Gnome’s app. The above is such an example, where matrices (tables) get annotations etc., such that I can keep track of indices and vector orientations, what refers to what.
It’s okay-ish, but maybe there is something better.
Suggestions, please, thanks in advance.
For a hand-written notes/whiteboard I use xournal++. I like that the notes can be separated to multiple layers. When I use it for a technical sketch it allows me to easily make several alternative designs in one file. Also it can open a pdf file as a background for the annotations.
One disadvantage is that it limits canvas size (to A4 I think) which sometimes get in a way of the “creativity”.
For diagrams I used draw.io but I cannot realy vouch for it since that was a long time ago and I did not use it a lot.
