As a system administrator, you can change the appearance of the Calendar List tab. For example, you can add or remove columns, change the horizontal alignment of values in each column, and set the default list sorting mode.
You can log on as the system administrator. Then switch over to the Admin screens and within the customization area click on 'Communication' and within that entity's context look at the List tab where you will find there is a new list called ‘CalendarList’.
And a system administrator can here control the behaviour of the list.
Note: You can add only the following field types to the Calendar List: Checkbox, Date Only, Date & Time, Email Address, Integer, Multiline Text, Numeric, Phone Number, Selection, Text, User Select, WWW URL.If you add a field whose type isn't supported, that field will not appear in the Calendar List.
You can also see the new System Action 'ResponsiveCalendarList' in the 'User' System Menu. This is the menu for the 'My CRM' context.