I've been using MYNetwork by the venerable Jens Alfke for an app of mine that allows devices to connect and share info over the network, it's actually a mission-critical part of the app. I tried writing my own wrapper for all of the C-level stuff you have to do for Bonjour, but it didn't work out so well, so I moved to MYNetwork.
It's been great so far, but the fact it's essentially opaque to me is causing trouble, as is that I want to move over to ARC once we can submit apps with it (there's a lot of Objective-C object references in structs, which ARC hates).
Can anyone recommend a similar wrapper, ideally that allows easy message passing between a client and a server over Bonjour as well as service discovery?