The Brave Browser offers a sync facility that keeps bookmarks and browsing history across Brave browser installations. So your data from phone, laptop or iPad could all become one. All at the same time respecting your privacy.
The current design of sync uses a device ID to identify a client. A client calls Brave server to store data. The first client creates the seed phrase of the sync chain.
The Brave server listens to these requests using a serverless component.