You can as add tags or delete them to these items. To remove a tag, first tap on it to select it. Then, tap on it again to deselect it.
- Empty circle - none of the selected items have this tag
- Gray circle - some items have this tag
- Circle with a checkmark - all selected items have this tag
While editing tags, you can add new tags. For this, tap on the "pencil" icon in the upper right corner of the screen.