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

Thank you Marko! I really appreciate it :)

And good luck with your company! That's my ultimate goal as well, to build a company full of skilled programmers, building useful software to make life easier :).

Best regards,
Juraj Mäsiar

Hello,
If you need help recovering your data, please contact me to my support email.
There are cloud backups so if you had your data in the cloud, they could still be in the one of the offline backups. Also, there are local backups that you could check as well - from the main menu / "History /backups".
Best regards,
Juraj Mäsiar

Hello,
It's fixed now in the new 16.1 version released yesterday.
Best regards,
Juraj Mäsiar

Hello,
Well, there is no such thing as standard HTML, especially when app like this one needs to store so much information (it's not just links and images).
But the good new is that the exported file is already a well structured JSON file that should pretty easy to parse and import into some other addon if needed.
I'm planning to add full synchronization with bookmarks so it will be possible in the future.
I would also like to say that as a 32 years "young" person I'm not planning to abandon this addon any time soon. Not to mention I'm using it daily myself and I can't imagine living without it :)
But it's good that you are thinking about backups!
Best regards,
Juraj Mäsiar

Hello,
If you have a feature request, feel free to write me email with detail description or create new feature request on my Github page:
https://github.com/fastaddons/GroupSpeedDial/issues
Best regards,
Juraj Mäsiar