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Didn't see the lenses in your link ... but if it's a telephoto/zoom lens, I would be hesitant as I doubt you could hold the iPhone still enough for a sharp image ... now if it's a macro/close-up you are trying to achieve ... get a magnifying glass from Radio Shack as it produces awesome images!! Check out these examples >> http://www.flickr.com/groups/424440@N23/pool/
 
Do you mean some kind of special magnifying glass for the iPhone or just any regular magnifying glass for macro....
 
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