While playing the Elite Dangerous beta, I stumbled across Zero-MQ (ØMQ).
ØMQ sounded pretty cool, so I ported one of my pet projects from using
homegrown socket communication to the much more feature rich libzmq.
I used the objc-zmq Objective-C language binding, prominently featured
on the ØMQ homepage.
This is a pretty uninspired wrapper, with a badly designed API and lots of bugs
on top. Quite soon I found myself spending more and more time
fixing bugs in the language binding rather than writing application code,
thus I started looking around once again. Luckily I then found
ObjectiveZMQ, which has a great API with a modern, sleak and
truly object oriented design. Used in conjunction with libzmq-ios it's pretty easy to get a cross-platform (OSX/iOS) app up and running in minutes.