After selecting a waypoint or multiple waypoints (see FAQ) and pressing this button, a label is added to the point.
You can choose from the following predefined tags:
Additionally, you can create a custom tag. Note that custom tags must not exceed 10 characters in length.
Viewing Tags:
After adding a tag, select the corresponding waypoint to see the tag displayed in the status bar at the bottom of the screen.
To view all waypoints and their associated tags: