Direct communication between iPhone users

I'm new to iPhone programming. So far I've only written a couple of simple apps just to get the hang of it. In a short time I will have an assignment to write an app that will let iPhone users communicate directly using short messages, and probably they will add a requirement to be able to send files to each other attached to the messages. Of course this sounds a lot like a mail client. For several reasons the client does not want to use mail, if possible, and attaching files would leave SMS mess开发者_如何学运维aging out. I've been reading Apple's documentation on local, push and broadcast notifications. Would any of these be the way to go?

Thanks

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User bonjour if you are one the same network: http://www.mobileorchard.com/tutorial-networking-and-bonjour-on-iphone/. Otherwise it sounds like you want to use Push. I'd recommend checking out Urban Airship