I have a Fastmail family account. This comes with a shared address book that all accounts in the family have access too; however, when I sync with DavDroid, only my personal address books are shown.
I contacted Fastmail and they replied with the following:
“Some clients don’t detect the shared address book correctly. So you would need to manually configure them.”
The reply also included instructions for manually adding the shared address book. This included a server address and username specific for the shared address book (which I don’t want to post here). There is an option to create a new address book with DavDroid, but I can’t add an existing one manually.
DAVDroid version: 1.0.7 (98)