How to setup Joomla CMS as a backend for iPhone app

I would like my iPhone app to get dynamic content off the net. This content should be managed using a CMS.

I have gone ahead and installed Joomla on my server and will be using the Joomla web interface to create and manage content.

I would now like the iPhone app to login to my server and fetch the content. I do not want the complete web pages for my iPhone app. Instead, I want the content in the form of XML or JSON or some serialized format so that I can use the data in a custom layout native to the app.

So I am looking for 2 things in particular: 1. How to setup HTTP based authentication for my iPhone app to access data from my server. 2. How to access the content in a serialized format (XML, JSON etc)

Are there plugins/extensions/components I can use to achieve the same.

Any advice on how this can be achieved would be helpful.

I am completely new to setting up/using CMS.

From serverfault srik

• I would use Osmek instead of joomla. Osmek is a cms that is specifically tailored to transfer json and xml through their api, so no hacking is involved. Their API is the base of their service, and works through an HTTP request via POST data.

  srik : although i was looking at setting up something at my own server using existing cms like joomla or drupal.. the free version of osmek serves the purpose for simple applications. thanks.
  From George Henderson