[Couchbase Lite architect here, so I have skin in this game] Even better, if you're using an open protocol, you can work with _either_ a hosted back-end or one

[Couchbase Lite architect here, so I have skin in this game] Even better, if you're using an open protocol, you can work with _either_ a hosted back-end or one you own, and move between them pretty easily. HTTP being a good example of course. The problem is that open protocols for general purpose data sync are pretty thin on the ground. Couchbase built our sync architecture on top of CouchDB's replication protocol, which was badly documented at the time but at least open. Couchbase Mobile (http://couchbase.com/mobile http://couchbase.com/mobile) uses this open protocol, so you can either BYO server (our own Couchbase Sync Gateway, or CouchDB) or use a hosted one like Cloudant. And you've got full access to the code (ours is all Apache licensed.) I can't say we're directly compatible with Parse, or trivial to migrate to (the data models and APIs are different), and I'm obviously biased, but I do think it's a good alternative to jump ship to.