To log a stay in the EU using the Visa Calculator:
Tap on Navigate on the bottom toolbar
Tap the first day you entered the EU on the calendar
Tap the last day you were within the EU
Tap submit at the bottom of the page
The number of days you can stay in the EU (highlighted in green below the calendar date) will update based on your entry.
Log a Visa day across months
To log a visa day across months:
Tap on the first day you entered the EU
Tap on the left or right arrow above the calendar to move between months
Tap on the final day you were within the EU
Tap submit at the bottom of the page