In the months since Apple released the iPhone and the iPod touch, Mobile Safari has become the most commonly used mobile Web browser in the United States, and its market share continues to increase. Because the iPhone’s form factor and user interface (UI) model are so different from other mobile browsers, many developers are choosing to redesign their Web sites to support Mobile Safari’s particular UI model.The decision to create custom content for the iPhone is the middle ground between two more extreme options. On the one extreme, you could do nothing. Mobile Safari’s tap-and-zoom interface is designed to allow users to easily browse Web sites even if the sites were not designed for mobile devices. Apple takes this route on the theory that iPhone users expect to access the full and complete Web. At the other extreme, you could use the newly released iPhone software development kit (SDK) to place your application on the iPhone natively. This gives you an immense amount of flexibility in your UI, as well as access to iPhone features ? such as the accelerometer or the camera ? that are impossible to use in a Web application. On the downside, the overhead of creating a native SDK application is higher than creating a Web application, and if you already have a Web application, creating a custom iPhone Web version is the fastest way to get a clean iPhone UI into your users’ hands.

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