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. Beware! 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.

NOTE: I've created my own fork which also has a branch for GNUstep (and which does indeed work on FreeBSD/GNUstep).