Add a Tag
To add a tag, click on a concept, click the "Color tag" button (Pic. 1) and then type in a name of the new tag (or select from the suggestions).
Pic. 1
All tags can be found under Pinned notes / Concept notes tab respectively on the left. (pic. 2)
Remove a Tag
To delete a tag, simly click on the x next to each tag. (pic. 2)
Pic. 2