iPhone Web applications are simpler to develop and deploy, while native iPhone applications can have much richer functionality.
You would generally prefer a native application when you need rich functionality and access to the device capabilities and resources, and also if you plan a mass distribution of the application through Apple's App Store.
On the other hand, if you don't have a Mac, you don't know Objective-C, or you need a cross-device application, you would probably go for a web application.
Tersus allows you to overcome most of the disadvantages of both native and web iPhone applications:
See Also: server access in native vs. web mobile applications
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