Firebase is a hosted service designed specifically for building real-time, collaborative applications. As a hosted, API-driven service it's easy to get started with and it handles scaling automatically. We're especially focused on keeping the API clean and easy to use. You won't need to worry about the mechanics of connecting to servers, long-polling, websockets, etc. Just drop in the library and go.

Real-time is at the core of Firebase -- it's designed to sync data fast enough that it's suitable for a whole new class of applications: multiplayer games, collaborative whiteboards, location services, and messaging apps.

Firebase is also designed for use across platforms and devices. Our JavaScript library supports the full featureset of our iOS and server libraries, so you can build apps that can communicate easily in real-time between the web and native mobile.

I was just going to post a shameless plug when I saw your comment. Here it is as a reply :)

If you are interested in transparent data sharing across devices, with realtime magic and fully offline editing capabilities, you might want to look at Couchbase for Mobile, a synchronizing NoSQL database for iOS (with Android coming soon). It is still pre-alpha but has an active community and is 100% open source (by the team behind TouchDB), so you can run it on your own servers.

https://groups.google.com/forum/#!forum/mobile-couchbase

/end shameless plug. Hope it is on topic for the folks reading this thread.

BTW download section on github has been deprecated https://github.com/blog/1302-goodbye-uploads.

The touchdb.org is pointing to download section for "Download Framework" link