I'm using Thunderbird and Android Contacts as client apps along with a owncloud 8 hosted remotely. I've activated the Contacts app on Owncloud and now I want to sync the contacts between all of these systems. What is the best way to do this? I'm trying to get Thunderbird sorted first. I've tried Addressbooks Synchronizer but this currently gives me either a message telling me that my credentials are wrong or sits silently doing nothing. I'm aware that this is a file sync, not record sync method, so it isn't ideal anyway. Is there a better, proper sync, method that I can use? I refuse to thing that this is an unreasonable request or that no one has asked it before me, but I just can't seem to find the answer. Thanks,Martin