Parse is a service that allows developers to build server backed mobile apps, without needing to build a custom backend. Parse makes it easy to throw in a data backend, freeing you to focus on building the front end.
ReactiveCocoa, you've heard about it, now try it out. This library might be the perfect starting place to get started on that app you've been wanting to build, using Parse, while using ReactiveCocoa, that library you've been itching to try.
Currently supports iOS, but I just got started. OS X next.
Pull requests welcome!