ICSx⁵ is an Android app to subscribe to remote or local iCalendar files (like time tables of your school/university or event files of your sports team).

GNU General Public License v3.0

icsx5

Elixir date recurrence library based on iCalendar events

MIT License

cocktail

A Java library for parsing and building iCalendar data models

BSD 3-Clause "New" or "Revised" License

ical4j

 :date: The VObject library for PHP allows you to easily parse and manipulate iCalendar and vCard objects

vobject

ex_ical

DAViCal is a server for calendar sharing. It is an implementation of the CalDAV protocol which is designed for storing calendaring resources (in iCalendar format) on a remote shared server.