Direct communications between iPhone users

[diego]

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 messaging out. I've been reading Apple's documentation on local, push and broadcast notifications. Would any of these be the way to go?

Thanks