trigger chat across multiple devices?

I am building up a chat app.

I am struggling with the idea of syncronizing the chat messages in real time.

My Scenario :

• trigger chat messages(incoming and outgoing) on multiple devices eg.Hangouts?


• synchronize chat activities in multiple tabs(web browser) eg.facebook ?

Is there any way this feature can be added to a chat application.

I am using mongooseIm(Erlang based chat server),strophe.js(xmpp client library),xmpp protocol.