icomet(https://github.com/ideawu/icomet) is HTTP a server-push comet solution, it supports all popular browsers and OSes, including Safari/iOS(iPhone, iPad, iPod), Safari/Mac, IE/Windows, Chrome, Firefox/Mac, Windows.
icomet is written in C++, built with libevent, and is totally open sourced.
Building a web chat with icomet is very easy, the provided JavaScript client library is easy to use:
var comet = new iComet({ channel: 'abc', signUrl: 'http://127.0.0.1:8000/sign', subUrl: 'http://127.0.0.1:8100/sub', callback: function(msg){ // on server push alert(msg.content); } });
You can see the Live Demo here: http://www.ideawu.com/icomet/chat.html