Install korganizer by entering the following commands in the terminal:
sudo apt update sudo apt install korganizer
Description:
calendar and personal organizer
This package contains KOrganizer, a calendar and scheduling program. . KOrganizer aims to be a complete program for organizing appointments, contacts, projects, etc. KOrganizer natively supports information interchange with other calendar applications, through the industry standard vCalendar personal data interchange file format. This eases the move from other modern PIMs to KOrganizer.
Homepage: http://kontact.kde.org/korganizer/
Version: 4:17.12.3-0ubuntu2
Section: universe/kde