My objective is to implement a messenger in a client/server model. However, in the clients, one client will be a web browser and another would be an android phone. So i need to develop an android app as well for a client. For web server I intend to use Lift with Scala. I wish to use Comet for messages in a fashion similar to described here http://simply.liftweb.net/index-2.1.html#Next
Although this technique might work fine in web browsers, I don't think it will work on the android app. What solution do I have for this? How do messengers like whatsapp work? Quickness in sending and receiving responses is an important factor here which is why I chose the Comet model ( and also its ease of implementation ). However, I'm open to new suggestions and ideas for incorporating this functionality. Please guide me through....I'm also open to other languages for the server that may be better suited to the task since I haven't started development.
Ignite Realtime has a xmpp library for android (and you can use openfire as server)
http://www.igniterealtime.org/projects/index.jsp
here about gtalk/hangouts https://developers.google.com/talk/