CouchDB already has embeddable ports to Android and iOS, and it has the added benefit of a built in master-slave or multiple-master replication system, so you c

CouchDB already has embeddable ports to Android and iOS, and it has the added benefit of a built in master-slave or multiple-master replication system, so you can have your app get and push up to date data from a server when a connection is available, but still be fully functional without it, for free!