Dates type pages can be configured to allow users to subscribe to events and appointments. For more information about integrating appointments (from the user's perspective), click here.
In the administration area, navigate to Pages & Menu. Select the desired dates page and click the pencil icon to edit it.
Place a checkmark next to You can subscribe to appointments and save the changes. All users with the necessary group assignments can now integrate the events and appointments on this page into an external calendar app via a link.