If two years ago I has suggested that mobile phones would soon sport 6.4-inch screens and processors more powerful than laptops you would have laughed in my face. Hell, I'd have laughed in my face. But that is exactly what Sony's new Xperia Z Ultra is. For a phone the Ultra boasts an almost ludicrously high-end specification - 6.4-inch screen? Check. 2.2GHz quad-core CPU? Check. 1920 x 1080 display resolution? Check. Waterproof and dust resistant? Check. Cor blimey as they used to say.
Make no mistake the Ultra is a big device - it's 179.4mm tall and 92.2mm wide which makes it quite the handful though at 6.5mm thick it is impressively skinny. At 212g it's not what you'd call light though. It's close to the weight of two iPhone 5Ss. That said it will still slip into the back pocket of a pair or jeans with ease, though I wouldn't suggest sitting down when it is - it fells very stiff and solid for such a slender bit of kit but I'd still be inclined not to try to stress it too much along the long axis.
Looking very much like a big Xperia Z1 or a small Xperia Z Tablet the Z Ultra has a truly huge screen, bigger even than the 6.3-inch screen on the Samsung Galaxy Mega 6.3. It's a very good screen too, using what Sony calls a Triluminos panel. What ever that is it addresses a traditional weakness of Sony mobile LCD displays; less than stellar viewing angle tolerances. This new panel puts Sony on an equal footing with the likes of Samsung and HTC when it comes to display quality: it's bright, colourful and very natural looking.
Some people may criticize the Ultra for having rather a lot of bezel at the top and bottom, but that does have a benefit, making the thing rather easier to hold in landscape for watching video or gaming and let's face it, if you want an Ultra you will be spending a lot of time gaming and watching video on it.
Thanks to the X-Reality engine (the latest version of what used to be called the Bravia Mobile Engine) videos and pictures look superb on the Ultra, they 'pop' in the same way they do on Samsung's S-AMOLED displays, but not as garishly. I like the Ultra's screen a lot.
With 16GB of storage, a Micro SD card slot and IP58-certificated resistance to water and dust ingress the Ultra is without doubt a versatile and robust old lump. It also supports LTE/4G cellular connectivity along with the very latest in Wi-Fi (802.11ac) and Bluetooth (v 4.0). There is also a Near Filed Communication or NFC chip.
Running the show is Qualcomm's new Snapdragon 800 chipset which makes the Ultra spectacularly fast. It's the first device ever to deliver AnTuTu benchmark numbers close to 30,000 which makes it the most powerful mobile device on the market, including the new iPhone 5S. The 3050mAh battery means you can actually use all the power and not have to recharge very few hours. In general use you should be able to get two full days from a charge.
The Ultra ships with Android 4.2 but Sony has already announced that an update to 4.3 will roll out in the not too far future. As is always the case with Sony they have re-skinned Android and added propitiatory media apps. Sony's music (Walkman), video (Movies) and gallery (Album) apps are very, very good and pay dividends on a device with a huge display like the Ultra. The loudspeaker is a bit puny but the sound through a good pair of headphones is excellent.
The only small drawback in the camera - an 8 megapixel affair with no LED flash. Frankly for this sort of price (buy one outright and you are looking at a £600 purchase) I expected the Z1's 13.1MP camera and an LED flash. Don't get me wrong, the camera does a perfectly decent job but it's still a mid-range component in an otherwise very high-end gadget.
Verdict. Very big, very powerful and very desirable, whip one of these things out in a bar and watch all your friends go wide-eyed as they take in the sheer size of the thing. The ultimate phablet? In a word, yes.
Price: £99 upfront on a £34 per month contract with 3 / £612 unlocked & SIM-free