A new breed of web applications are being brewed but some apps only work for the iPhone. When you view the applications using your browser, these iPhone-exclusive apps will display a different page. One such application is PocketTweets, an iPhone Twitter client.

So, if you want to be able to use these iPhones-only web applications, here’s what you can do:

1. Download Firefox.
2. Install the Firefox add-on named “User Agent Switcher”.
3. Using the “User Agent Switcher” add-on, add a User Agent and call it “iPhone” (but you can call it whatever you like) and add this string “Mozilla/5.0 (iPhone; U; CPU like Mac OS X; en) AppleWebKit/420+ (KHTML, like Gecko) Version/3.0 Mobile/1A543a Safari/419.3″
4. Save and switch to the iPhone User Agent before going to an iPhone-only site

Here’s a screenshot of PocketTweets running on Firefox 2.0.0.5.

Enjoy!