How does one build an app like eClicker?


I’m interesting in building an app for meetings where a dozen (say) attendees could use their phones and iPad for joint planning. I’d need them to talk to each other and want to use one of the iPad as the “controller”.

What I’m wondering is how one goes about creating apps that talk to each other over the local network - similar to what the eClicker sweet seems to do. Is there a recommended approach, set of third party libraries, etc? Anyone know of any good online tutorials that go through the basics of building such an app?