i have built similar thing long time ago, using couchdb as replication-storage mechanism, and it's variants on non-server platforms - touchdb/android/ios <-> po

i have built similar thing long time ago, using couchdb as replication-storage mechanism, and it's variants on non-server platforms - touchdb/android/ios <-> pouchdb/js-browser etc , but yes, except serverside, all other platforms still had sqlite underneath. Long live sqlite :)