Lightning
Open Source
Lightning App Builder is a point-and-click tool that makes it easy to create custom pages for Salesforce1 and Lightning Experience.
Kontact
Open Source
Kontact is a personal information manager and groupware software suite developed by KDE. It supports calendars, contacts, notes, to-do lists, news, and email.
Rainlendar
Freemium
Rainlendar is a calendar program for Windows, Mac OS X and Linux.
Compare Fantastical with alternatives
Compare Lightning and Fantastical and decide which is most suitable for you.
Compare Rainlendar and Fantastical and decide which is most suitable for you.
Compare Kontact and Fantastical and decide which is most suitable for you.