I had the same problem where I was able to enter my account in davdroid and Davdroid itself successfully found all my calendars, however none of them would sync with the phone’s calendar programs (both the native calendar and e-tar). Seems like a bug / change in android 7 broke calendar syncing. I was unable to get davdroid to work for months, however now that there’s a new DAVx5 client I decided to try it. They fixed it! The link is broken in the fdroid repo’s BTW, however I managed to install davx5 manually and everything’s working. So if anyone else has the same issue, give the new davx5 a shot!
DAVdroid doesn't work with citadel-server
This URL is not reachable and even if it was, I wouldn’t have user name and password.
Please provide steps to reproduce. Can you also provide a Citadel test account?
You can create an account on the project’s website http://uncensored.citadel.org
I can confirm this bug!
DroidDAV does not work with citadel
More information about citadel groupdav support:
An demo account can be created on uncensored.citadel.org.
It seems like Citadel doesn’t provide a CalDAV/CardDAV (which is not GroupDAV) service: » If and when CalDAV clients become generally available in a meaningful way, we will of course provide a server implementation of it. In the meantime, GroupDAV is available.«