Video description: Here's another quick hack to add more physicality to touch screen displays. With a small knob, it's natural to grab it such that your fingers actually touch the screen making it nothing more than a physical prop to provide some tactile feedback. We experimented with conductive fabrics, copper tape, etc., but found that it worked best with simple physical objects.

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<a href="http://dailyiphoneblog.com/2010/05/14/iphone-physical-touchscreen-knob/">

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