Welcome to Firefox for Android Add-ons.
Add extra features and styles to make Firefox for Android your own.
CloseReview for Addressbooks Synchronizer by impelf
Rated 5 out of 5 stars
This is excellent! I finally found something that can sync my contacts in Thunderbird!
I had earlier tried Sync Kolab, which is buggy (my deleted contacts keep reappearing in a refresh!!)
To create your own collections, you must have a Mozilla Add-ons account.