TestiPhone is a web-based simulator for rapid testing of applications in the iPhone. This tool can be used in Internet Explorer 7, FireFox 2 and Safari 3 on Windows, but it is best to have Safari to have a more realistic experience.
The simulator works almost the same way: it does not have Flash or Java plugins like any other browser used on a computer; hides the scrollbar like the iPhone it does, which only appears when you swipe your finger across the screen. The only thing that makes it different is that it does not have zoom like the one that the phone brings.
Via | iPhoneLand