How to synchronize CalDAV and CardDAV with Android
caldav and carddav are the protocols for calendar and contacts data, respectively. caldav can be used for both calendars and tasks, while carddav is entirely for contacts.
Tags : caldav
How to set up IMAP / POP, CalDAV or CardDAV accounts on iPhone or iPad
if you don't use a large online service provider, you can still set up and use any standard email, calendar, and / or directory services you like, including your own online