Has Sony's 6.4-inch Xperia Z Ultra crossed a line in screen size?

<i>The Independent</i> was the first to see Sony’s new is-it-a-phone-is-it-a-tablet hybrid for review. <b>David Phelan</b> reports

If, Sony, the word Ultra suggests you won’t be making a phone with a bigger screen than this one, that’s a good thing. The Xperia Z Ultra is so huge that it’s a two-hand machine. But although it has a record-breaking size display for a mobile, this phone isn’t too big to use. I mean, it comes close…

The 6.4in display on the Ultra is plenty big enough for this gadget to work as a tablet. What saves it from being unwieldy is the handset’s thinness. It’s just 6.5mm from front to back, which means that it’s the world’s thinnest Full HD display phone, Sony boasts.

The thinness means you can grip the Ultra with reasonable ease, unless you have small hands, in which case you may have to look elsewhere. But it’s startlingly easy to get used to this phone’s size.

Not least that’s because this is a beautifully styled handset, with an effortless premium feel and smoothly rounded edges that make it highly tactile. It’s like the earlier Xperia Z, but classier.

That Full HD resolution on the screen, combined with knowhow borrowed from the guys at Sony who make Bravia TVs, add up to a highly watchable display. It’s sharp of course – the same number of pixels as on a full-size flatscreen telly – but it’s also rich, colourful and contrasty. An image processing engine aims to make standard definition content look as good as it can here and HD video really gleams. So you can download and watch a whole movie without too much trouble. It’s a highly immersive experience. I’d recommend plugging in headphones, though, as the single mono speaker is only average.

Maybe that’s because the phone is waterproof, like Sony’s earlier Xperia Z and Xperia Tablet Z. This means that the microUSB socket and sim card slots are hidden under flaps. But at least the headphone socket doesn’t have a protective flap over it so listening to music is faff-free. And somehow Sony has worked its magic so this apparently open socket is waterproof, too.

There are other innovations on board, like the way you can write on the screen using a regular pen or pencil. This is cool for scribbling notes or drawing stuff, though frankly the keyboard is pretty good here so the need to write instead of type is limited. A bonus of lots of screen real estate is that the keys are widely spaced.

Another benefit of a phone this size is there’s room for a big battery. So the Xperia Z Ultra keeps on going for a full day with ease. And that’s despite a powerful processor beavering away to keep the screen looking smooth and stutter-free. The Qualcomm Snapdragon quad-core chip is one of the most potent yet seen on a phone.

In fact, the only real downside to a phone this big is you feel a bit of a chump squeezing it against your ear to make a phone call. Oh yes, and it doesn’t feel safe to slip it into the back pocket of your jeans lest you sit down hard on it.

Sony’s take on Android is as accomplished and stylish as ever, with demurely coloured icons contrasting strongly with, say, Samsung’s super-bright elements.

The size will be the element that decides whether this is a phone for you or not. And if you don’t mind it, it may well mean that you won’t need a tablet to go with it. For many, though, this will be a size too far.

Sony Mobile has a strong range of mobile devices at the moment. They look good, work well and have great features. And if rumours are to be believed, IFA, the big electronics show to be held this week in Berlin, will have more stand-out Sony Mobile announcements. The company is on a roll.