Review for TbSync by Peter Kendall
Rated 5 out of 5 stars
This, and its partner add-on Provider for CalDAV & CardDAV, worked first time with a simple to use Graphic User Interface. The only wrinkle appears to be caused by Apple ceasing CalDAV support for their Reminders iPhone app but unchecking that box fixed things and calendar event alerts do sync in any case. Worth the donation.
This review is for a previous version of the add-on (2.16).To create your own collections, you must have a Mozilla Add-ons account.