Following reports, Nokia's own teaser campaign, and a last-minute leaked image, the Lumia 925 is official today. The Finnish smartphone maker is taking the wraps off its latest flagship Windows Phone, and there's a slight twist: it's made from aluminum. Nokia's latest smartphone is trading a full polycarbonate unibody for an aluminum casing. It's not fully metal — the rear of the device will be polycarbonate, and the front is naturally made of glass — but it marks a new shift for Nokia's Windows Phone design.

A Lumia on a diet

Nokia has slimmed down its Lumia flagship to just 8.5mm and a weight of 139 grams. Compare that to the 185 grams and 10.7mm thickness of the Lumia 920, and it's clear the company has focused on size and weight here. The aluminum frame, which runs around the outside of the body, helps to bring the weight down. The design includes a rounded outer frame that meets the polycarbonate rear. Nokia's positioned its rear camera in a little hump, presumably to push the overall device weight and thickness down.

The specifications are largely the same as the Lumia 920. The Lumia 925 will come equipped with a 1.5GHz dual-core processor, 1GB of RAM, and 16GB of storage (some carriers will have 32GB variants). In fact if you simply glanced at a spec sheet then you might struggle to see the differences, but there are some subtle changes that make this stand out with an entirely new design.

The changes are really apparent on the outside of the device. Nokia has equipped the Lumia 925 with a 4.5-inch OLED display running at 1280 x 768 resolution. The same 8.7-megapixel PureView camera is present, with a 1.2-megapixel forward-facing camera available too. Optical image stabilization, and dual-LED flash carry over from the Lumia 920, but the real change is an additional lens on the Lumia 925. Nokia has added a sixth Lens to its five plastic lenses, this time opting for a glass physical lens.

Nokia focuses on imaging, adding an additional lens

The change will combine with a new Nokia Smart Camera mode, that can be made to be the default camera on Windows Phone. It alters the onscreen camera UI and allows owners to take 10 images with a new motion focus feature that lets users blur, remove, or alter images in the background. Imaging, like the Lumia 928 and Lumia 920, is a big focus for Nokia's latest Lumia. When the device is made available in June, both Nokia and Microsoft will market its camera capabilities. Nokia is also signing a strategic marketing partnership with Warner Brothers for the upcoming Man of Steel movie. Lumia 925 owners will get exclusive Superman content as part of the deal — a fitting partnership for its new metal Lumia.

Coming to T-Mobile in the US

Imaging aside, Nokia is making colors and wireless charging an optional part of the Lumia 925. The company was quick to launch its Lumia 920 with a range of vibrant colors, but the Lumia 925 will only be available in grey and black metallic colors. If you want wireless charging, or a colorful body, then you'll need to purchase an additional sleeve that attaches to the rear of the device (like the Lumia 720). They'll be available in red, yellow, black, and white. Nokia isn't discussing exact worldwide pricing or availability, but the company says sales will start in the UK, Germany, Italy, Spain, and China in June. The US will follow the initial debut in June with a launch on T-Mobile, and Nokia will price the Lumia 925 at 469 euros in Europe.

Hands-on impressions and photos of the Lumia 925