Rated 4 out of 5 stars

I can finally sync Ubuntu 16.04 running "radicale" with Android CardDAC-sync, fantastic, thank You VERY much!

But I have two issues:
1) CardBook restricts address auto-completion to CardBook; I did not find a way to include my local Addressbook when adding emails.
2) Editing and management in CardBook is not as convenient as the built in Address Book. While I understand that the VCARD standard limits the field, editing, searching and grouping in CardBook is much more difficult.

If CardBook could use the already existing AddressBook implementation, and just add another Book, I think this would be ideal.

This review is for a previous version of the add-on (11.2). 

1/ it is possible : in CardBook preferences, in the first tab uncheck the value of "CardBook as unique source"
2/ I will try to improve this point