EDIT:
Regarding your question - the synchronization is automatic, just login to the same account on all devices:
https://group-speed-dial.fastaddons.com/
I hope this helps :)

Hello,
The synchronization is not paid :).
There is only few Pro features, all listed here:
https://github.com/fastaddons/GroupSpeedDial/wiki/PRO-version-features

Most of the features including all Cloud synchronization and backup is forever free!
Best regards,
Juraj Mäsiar