I use PouchDB for this exact use case and it works great. It solves the storage and replication problems both. If you build it upon SQL, you would also need t

I use PouchDB for this exact use case and it works great. It solves the storage and replication problems both. If you build it upon SQL, you would also need to create a CRDT schema to make replication sound. That's probably more work than just using REST/GraphQL/RPC. Local data is king. Especially as the network connection degrades.