Using .Mac Reader on Firefox

Along with the release of the iPhone, Apple also introduced a web application dubbed .Mac Reader. The purpose of .Mac Reader is to allow RSS feeds to be viewed using the iPhone.

Unfortunately, the application is restricted to use on the iPhone. Attempting to use any other browser to access .Mac Reader results in an error. However, getting around this restriction is relatively easy. These instructions will show you how.


To access .Mac Reader, two things are required: Firefox along with User Agent Switcher (install), an incredibly useful extension.

User Agent Switcher is a tool that has the ability to change the user agent Firefox reports to web servers. Doing so allows us to “spoof” the browser, effectively appearing as a different browser altogether.

iPhone User-Agent

In this particular case, we want to appear as the iPhone, which has the following user agent:

Mozilla/5.0 (iPhone; U; CPU like Mac OS X; en) AppleWebKit/420+ (KHTML, like Gecko) Version/3.0 Mobile/1A538a Safari/419

User Agent Switcher is configurable through the Tools menu. An entry for the iPhone should be added to the list of User Agents.

User Agent Switcher

The entry for the iPhone should contain a description and a user agent exactly as printed above.

Add User Agent

As a convenience, I’ve created an XML representation of the iPhone user agent that can be imported into User Agent Switcher.

.Mac Reader Protocol

Now that we know the iPhone’s user agent, we need to understand the protocol used by iPhone to fetch feeds with .Mac Reader. The protocol is a simple HTTP request with the location of the desired RSS feed contained within the URL. The general format is as follows:[url-of-rss-feed]

For example, the URL used to retrieve the RSS feed of this site would be:

However, attempting to access that URL within Firefox (or any non-iPhone browser) will generate an error informing us that “This application can only be viewed using the iPhone.”

.Mac Reader Error

Firefox Access

In order to access .Mac Reader using Firefox, we must trick the server into thinking that Firefox is really an iPhone.

To accomplish that, we need use the iPhone’s user agent when requesting pages. iPhone should be checked under the Tools > User Agent Switcher menu.

User Agent Switcher Menu

Now, when accessing the feed, it should appear as it would on the iPhone.

.Mac Reader Feed


Lonna Hanson
July 3, 2007 at 6:15 PM

Very interesting, Jared. I am amazed with what you know. Wow!

July 4, 2007 at 11:51 AM

Thank you for the information about the URL Syntax for the reader. I got so far that I spoofed the User Agent(got it from , “optimize for page readability”) , but I don’t have an iPhone to figure out the URL Syntax. Thanks for that!

July 7, 2007 at 1:45 PM

Thanks for the import file. Saved me some typing :-)

July 8, 2007 at 9:53 AM

Yes, thank you very much for the XML file, very useful.

February 10, 2010 at 6:04 AM

It looks as though Apple has taken out this functionality over the past day Feb 09,2010. Jared do you have any insight to make it still work?

I amazed on your knowledge of this functionality as well.

Great info!

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