Prototype of the iPhone 5 is rumored to be using metal chassis on the back and use a larger screen as seen on Foxconn, according to 9to5Mac.
Although some reports claim that the iPhone 5 will adopt a curved metal chassis, our sources say that the model of the iPhone 5 looks to continue using flat chassis models. Whether the material is made of metal chassis will still uncertain. We think that the iPhone 5 seems to be using aluminum chassis, but the heart we want to see the iPhone 5 using a metal chassis.
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Sources of 9to5Mac says that iPhone 5 will soon go into mass production stage.