With Mood Tracker, you can describe your day visually, so as to look back through dates on your calendar. Some people like to use this every day, to then look at a visual progression on the calendar, while others use it to mark special days to get back to more easily, like a birthday or special occasion.
To use the mood tracker, click on the star next to the date on the toolbar, and select an emoji from the drop-down.
Alternatively, click on the same star icon on any entry on the sidebar, and then select an emoji from the drop-down.
Click on Remove to remove the mood emoji from this day.