Apple has launched a directory of applications specifically made for or working with the iPhone and the iPod touch.
It features web-based applications and widgets only such as FaceBook, Big Bang Sudoku UltraLingua Mobile, Digg iPhone Application and SmugMug.
It is available on Apple's web site through the following URL:
The company was recently rumoured to be preparing a true development kit for standard iPhone applications which run directly on the system instead of running through the web on Safari.

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Looks nice, try
Looks nice, try http://appsafari.com for a more updated list of iPhone apps