Rated 5 out of 5 stars

works fine and is easy to use.
But it does NOT seem to SYNC across machines. Or am i doing something wrong?
Installed TBSYNC + CalDav/CardDav+ Catagory Manager on multiple machines, and using the same Google Account.
I created categories on one machine, they do not sync to the other ones.
any possibility to do that?

This review is for a previous version of the add-on (4.0). 

Sadly google sucks, they did not implement the full CardDAV spec and do not sync these groups/categories. They only do that in their own proprietary google API (which TbSync is not using). Any other CardDAV provider will do.