Sony Mobile has announced the launch of its new flagship smartphone for 2013, the Sony Xperia Z.The new phone, a mammoth 7.9mm thick, 5-inch beast, has previously gone under the guise of the Sony Yuga and enjoyed the usual array of leaks ahead of its unveiling at CES, where Sony has finally made the phone official.READ:\u00a0Sony Xperia Z release date UK: 1 March says Phones4U, mid-Feb says CarphoneCalled the Xperia Z - because, according to Sony, everything before has been a build-up to this moment - the new smartphone will go on sale in the UK in the coming weeks, with mobile phone operators including Vodafone all keen to stock it in white, black and purple.The phone itself, which Pocket-lint has already had a chance to play with, measures\u00a0139 x 71 x 7.9mm and weighs\u00a0146 grams, and comes with a Full HD 1080p Reality Display with Mobile Bravia Engine 2 that builds on the technology found in the company's 2012 range of phones.That screen, which is as stunning as it looks in our hands-on pictures, is the main focus of the design, with the casing emphasising Sony's "OmniBalance" approach that means it looks the same from all angles.That means the front is void of all buttons and fixtures aside from a front-facing camera and the Sony logo. It's the same for the back - and, for the most part, the sides - with Sony opting to cover all the ports to create not only an almost seamless design, but also one that is waterproof. Yep drop it in the swimming pool, or more likely the toilet, and it'll be fine.There is one feature that breaks away from the smooth lines, and that's the rather large aluminium power button on the right. It's an interesting choice, but one that feels well-made and comfortable to use. It's the phone's worry button and many will welcome that.READ:\u00a0Sony Xperia Z: Details worth examiningOf course that 5-inch 1080p 443ppi display (a lot more than most phones on the market) is big - like, really big as our hands-on pictures show - and like the Samsung Galaxy Note II makes phones like the iPhone 5 and even the Samsung Galaxy S III look tiny by comparison.Surprisingly it's not quite as big as we were expecting, with the screen real-estate smaller than the SGN2 and the casing (just 7.9mm thick) keeping the size to a minimum as much as possible. Interestingly the Sony Xperia XL, also announced at CES 2013, comes with the same display in a smaller non-waterproof housing, but Sony has confirmed to Pocket-lint that it won't be coming to the UK.But it's not just a big screen. There is power behind the Xperia Z too in the guise of the latest Qualcomm Snapdragon processor - the 1.5GHz asynchronous quad-core Snapdragon S4 processor with 2GB RAM - a 13-megapixel fast-capture camera, 4G LTE, NFC, and a 2400mAh battery which, with additional help from a new software feature from Sony, should give you more than nine days of battery life. We're thinking standby, not active use here.In our play with the new phone it is certainly zippy, happily coping with anything that was asked of it. Video plays beautifully with the big, bright screen really shining - we watched a little bit of Skyfall of course (it is a Sony picture, after all).Where Sony is hoping to succeed - and for the most part appears to from what we garnered in our play - is in finally utilising all the experience from the other divisions in the company.The screen quality comes courtesy of the TV division, with every trick learnt with the latest Bravia range employed here. The air gap to reduce reflection when you are out and about has been borrowed from the company's TV range, as has the processing engine behind the graphics and colour reproduction. There is even technology in the phone that tries to enhance your footage to make it better in the same way televisions do. And it shows. The picture quality of the Xperia Z is very, very good.It's the same when you get to the camera. Again Sony Mobile has turned to the Cyber-shot team at Sony to help create what looks to be a great camera. We weren't able to take away any shots for further analysis, but our play of the camera on the phone in our demo tells us\u00a0there is plenty to like. As before, the interface is clean and easy to use with the option to customise shortcuts on the camera screen for your favourite features.Sony has opted for an Exmor RS for mobile, the world's first image sensor with HDR (High Dynamic Range) video for smartphones, alongside the usual array of burst modes (10 pictures at 9 megapixels) and scene modes to help you get more out of the camera.There are 30 scenes to choose from, although for the most part you'll probably just want to opt for the new Superior Auto mode that automatically picks the right scene for the job. Whizzing it around quickly in our demo the camera did well keeping up between portrait, macro and landscape modes.Even the Walkman and PlayStation get a look in with dedicated music player and PlayStation-certified stores and games waiting to be played.\u00a0"The Walkman application provides access to all your downloaded music, a library of 18 million songs to explore from Music Unlimited and Facebook social integration," Sony tells us. "The Movies application gives consumers access to over 100,000 movies and TV series from Video Unlimited while the Album application enables easy access to Facebook friends\u2019 photos as well as browsing photos by location."There's the usual array of boring acronyms included too. A 3.5mm headphone jack (concealed), DLNA, aGPS, Bluetooth 4.0, GLONASS, HDMI support, microSD card slot up to 32GB. There is up to 16GB of memory and the battery isn't replaceable.\u00a0Add in NFC that plays nice with the newly-announced NFC-ready Bravia televisions at CES (users will simply touch Xperia Z to the remote control of the TV to instantly enjoy photos and videos on the big screen), LTE for all networks including the yet to be released Vodafone and O2 4G, and it's looking good.All that tech requires a big battery, in this case a 2400mAh offering and the addition of a Sony unique feature called Stamina Mode.Battery Stamina Mode works automatically to shut down battery-draining apps whenever the screen is off and start them up again when the screen is back on.If it works as Sony say it does - and there's no reason not to believe it - it's going to be a must-have feature and one all phone users will want. You can customise individual apps to be controlled by the battery-saving feature, which will make life easy.It means that if email is important to you, but Twitter isn't, you can have one work as normal, while the other doesn't drain the battery in the background. Clever.What's the catch? It is probably that for many the phone will be just too damn big. It's not heavy, which has a lot going for it, and it is smaller than the SGN2, but we don't suspect many women will be champing at the bit to get one in their handbag.\u00a0The Xperia Z we played with came with Android 4.1 Jelly Bean installed with the normal Xperia UI, but Sony has confirmed that the Xperia Z will be upgraded to 4.2 shortly after launch.