The back plate for the next-generation iPhone appears to have been leaked, with new images showing taller iPhones with a metal back which could come in various colours, as well as several other tweaked features and design elements.

The images show two iPhone back panels, a black and a white model, with a large portion of made out of an aluminium alloy. The metal antenna band is molded into the back plates, says 9to5Mac, creating a unibody enclosure, leaving more space for internal components. Apple could use this space for a bigger battery, and to introduce LTE 4G to the iPhone.

9to5Mac first saw the photographs of the unreleased iPhone’s back plate in iFixyouri’s parts catalogue. The iPhone repair experts said that they received the back plate from a Chinese parts supplier.

iFixyouri suggests that the black and white iPhones shown in the photographs won’t be the only colours available for the new iPhone. There are apparently at least two other colours for the back plate, says the company, which 9to5Mac points out was the first to correctly reveal that the iPad would be available in white.

The photographs also show a smaller dock connector, a feature that has already been rumoured to be coming to the next-generation iPhone. The headphone jack, which has always previously been positioned on the top of the iPhone, appears to have moved to the bottom of the device.

The speaker grills also have a new design, and there could be a second microphone positioned next to the rear camera for improved audio recording.

9to5Mac has also revealed photographs of what is believed to be the next-generation iPhone’s frame, which still has a home button, but matches with the rumours that the device will be taller, keeping the same width as the iPhone 4 and 4S.

A photo of the new iPhone’s front panel shows that the FaceTime camera has moved above the earpiece, but it doesn’t show an edge-to-edge touchscreen design, something that many believed would arrive with the next iPhone.

A second set of images showing the same back plate has emerged from uBreakiFix.com. Engadget points out that the part could be from an early engineering prototype, but highlights that the parts appearing on 9to5Mac too means that these photographs could be the real deal.

As for release dates, new reports suggest that the next iPhone will arrive in September or October.

CNET reports that RBC analyst Amit Daryanani has said that the new iPhone will have 4G LTE, will be redesigned and will launch by October.

“Since the launch of the original iPhone, Apple has updates the product annually and has redesigned the phone every two years,” wrote Daryanani in an investor report on Tuesday. “In our view, consumers are becoming aware of the product cycle and we believe this should cause increased seasonality in the product as consumers await updated and fully remade iPhones.”

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