Until now, if you lost or broke your phone, your Signal message history was gone, a real challenge for everyone whose most important conversations happen in Signal. So, with careful design & development, we’re rolling out opt-in secure backups.

Secure backups will let you save an archive of your Signal messages remotely in privacy-preserving form, refreshed daily.

Now available in the latest Android beta release, rolling out to iOS & Desktop soon

https://signal.org/blog/introducing-secure-backups/