iPhone 5 using metal chassis and a bigger screen?

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.

The next major improvement is the larger screen. Digitimes states that the iPhone 5 screen will appear increase to 4 inches; 0.5 inches larger than the iPhone 4. Our sources do not have a definite size of iPhone 5, but apparently iPhone 5 screen will be larger than the iPhone 4.

Sources of 9to5Mac says that iPhone 5 will soon go into mass production stage.