Parse.com has recently launched Cloud Code. Cloud Code lets you host cloud functions on the Parse Cloud accessible to your Parse clients. This video demo/tutorial below shows what Cloud Code is and why/when it would make sense to use it.
Parse is a Backend-As-A-Service solution for your mobile applications – no need for server side coding! Check them out at http://parse.com
There are a bunch of cloud services out there offering the promise of letting you build applications without server-side coding. Each have different flavors. Firebase approach takes advantage of the idea of subscribing to data and reacting to changes to this data by setting up callbacks in your client-side coding. In the video below, I quickly walk through the benefits of using Firebase if you intend to use collaborative and real-time applications. After watching the video, give Firebase a spin, at http://www.firebase.com