It's worth noting since iOS 5 and 10.7, Apple includes the NSJSONSerialization class which I've seen to be much faster than 3rd party libs, and are now "the way

It's worth noting since iOS 5 and 10.7, Apple includes the NSJSONSerialization class which I've seen to be much faster than 3rd party libs, and are now "the way" to decode JSON in obj-c. As far as using something like JSON (in a general key/value sense) in a TCP stream, to disk, etc., I have some bias towards using something a friend made called "KeyedBits" up on Github.