Backups & read replicas are the primary use cases. If you're interested in local-first, you can check out projects like cr-sqlite[1].
Can this be done with only Litestream, or is LiteVFS still in development? I looked into this last year but was put off by LiteFS's stated write performance penalty due to FUSE [1]; it's still marked as WIP [2] and hasn't seen updates for over a year.
[1] https://fly.io/docs/litefs/faq/#what-are-the-tradeoffs-of-us...