Today was the day of Nokia's big event in London, and as promised the Finnish firm showed off "what's next" for its Lumia line. Nokia officially took the wraps off of the Lumia 925, a new Windows Phone device that features an aluminum outer frame and a polycarbonate backside. The body of the Lumia 925 measures in at 8.8mm thick and weighs 139 grams, quite a bit thinner and lighter than the Lumia 920, which comes in at 10.7mm thick and 185 grams.

The new Lumia 925 sports a 4.5-inch 1280x768 AMOLED display and 1.2-megapixel wide-angle camera on its face, as well as an 8.7-megapixel PureView camera around back. Buried inside the 925's aluminum and polycarbonate body is a 1.5GHz dual-core Snapdragon processor, 16GB storage, 1GB RAM, NFC, 4G LTE connectivity and a 2,000mAh battery powering the whole show. There's no wireless charging built in, but Nokia will be offering yellow, red, white and black plates that can attach to the Lumia 925's rear and provide wireless charging capabilities.

Getting back to that PureView camera, the Lumia 925 is the first Nokia device to feature the company's new Smart Camera app. Smart Camera can burst capture 10 shots at once (each one being a 5-megapixel image) and then allow the user to edit them with features like Best Shot, Action Shot, Remove Object and Motion Focus. The good news for existing Lumia owners is that Nokia plans to bring its Smart Camera app to other Windows Phone 8-powered Lumia models as part of an "Amber" software update that'll begin rolling out in the summer. Nokia also announced that the new Oggl photo-sharing app from Hipstagram, which supports sharing to Instagram and other social networks, will be available on its Lumia smartphones.

As for the camera itself, Nokia has packed its usual bag of features into the PureView-branded 8.7-megapixel shooter. Users will find autofocus, a dual LED flash and optical image stabilization all baked into the Lumia 925. 

The Lumia 925 is slated to begin rolling out around the globe in June, hitting the U.K., Germany, Italy, Spain and China first, followed by the U.S. Some of the carriers that'll be launching Nokia's new Lumia include Vodafone, China Unicom, China Mobile and T-Mobile U.S. Pricing for the Lumia 925 is expected to be set at approximately 429 euros (around $557.70 dollars).

Nokia has been using polycarbonate materials on its Lumia smartphones since the debut of the Lumia 800, but the Lumia 925 changes things up a bit by adding an aluminum outer frame. This As a result, the Lumia 925 is considerably slimmer and lighter than its Lumia 920 sibling, which addresses two of the complaints that many people had with the that model. The fact that the Lumia 925 is launching on T-Mobile in the U.S. is also big news for Nokia, as it means that the Finnish firm has a flagship Windows Phone device on three of the top four major U.S. operators.

Overall the Lumia 925 looks to be Nokia's best Windows Phone offering yet, offering a PureView camera and 4.5-inch AMOLED display in an aluminum frame that's both thinner and lighter than its predecessors. While the device 925 isn't likely to light a spark under Windows Phone's adoption, it's big for the platform to have a high-end Lumia on another major U.S. operator and several other carriers around the globe. There's no word yet on exactly when the Lumia 925 will launch on T-Mobile and its other operators, but with a rollout slated to start in June, it shouldn't be long before we hear more. Stay tuned.

Via Nokia, Nokia Conversations (1), (2)