Here's an example of what can be quickly created using the TeagueProtoJS framework for WebApp UI prototyping. The iPhone OS is mocked-up as a webpage, added to the home screen as a application, and then reloaded in full-screen mode. The entire application was built in about 3 hours; this is just an example of what you can quickly do with WebApps as a form of UI prototyping on mobile devices.
Check out the code and try it yourself at http://labs.teague.com
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