Let's have a look at how Apple new flagship smartphone - the Phone 5S - matches up:
Look and Feel
Borrowing much from the squared, industrial design of the HTC One and iPhone 5S, the Xperia Z is all 90-degree angles and flat surfaces, with glass on its front and back and soft-touch plastic around the edges.
At 7.9mm the Xperia Z is almost exactly the same thickness as the 7.6mm iPhone 5S, but with its 5in screen a full inch larger than the iPhone's Sony has done an impressive job to keep the phone's thickness in check - although at 146g is weighs 34g more than the iPhone 5S.
Like the iPhone, the Xperia Z's squared-off design makes it slightly less comfortable to hold than the curved HTC One, but that's almost a non-issue, and the Xperia's Z's party trick of being both water- and dustproof makes up for this minor shortfalls.
But waterproofing comes at a cost, and that is the need for removable plastic flaps covering the microSD card slot and micro USB charging port. In a world where a smartphone's looks are as important as its performance, fiddling around with tethered plastic flaps feels like a step backwards compared to the iPhone 5S's clean cut, industrial design.
As for a party trick of its own, the iPhone 5S has a fingerprint reader on the Home button. Instead of entering a PIN or password, users can simply touch the button to gain access to their phone; the reader can also be used to confirm purchases on the iTunes Store instead of entering a password.
The Xperia Z has a 5in screen with a full HD resolution of 1080 x 1920 giving a pixel density of 441 per inch. This is more in every regard than the 4in iPhone 5S, which has a resolution of 640 x 1136 and a pixel density of 326 per inch.
Howvere, resolution and pixels densities this high don't need to be compared too closely - you can't see individual pixels on either phone. More important is screen quality, and for this the Xperia Z is a mixed bag; borrowing technology from Sony's Bravia television range, the Z is bright and sharp, but its TFT panel appears washed-out and with less contrast than the HTC One and iPhone 5, which shares its screen with the iPhone 5S.
Like most high-end Androids, the Sony Xperia Z has a 1.5GHz quad-core processor with 2GB of RAM which sees the phone perform excellently. But, due to Apple's unwillingness to disclose details of its new 64-bit A7 system-on-a-chip, other than to say it is two times faster than last year's A6, it isn't really possible to compare the two processors in a quantitative way.
Safe to say though, the smartphone industry is at a stage now where consumer interest has turned away from specifications and towards camera quality and hardware design, as once you get to devices like the Xperia Z, iPhone and high-end Samsung Galaxies, differences in overall performance are all but impossible to spot.
The only meaningful difference is that of storage. Where the Sony - and Samsung Galaxy S4, for that matter - have microSD card slots to boost storage by up to 64GB, the iPhone 5S does not, limiting it to 16GB, 32GB or 64GB depending on the model you buy; it's disappointing to see that Apple is yet to introduce a 128GB version of the iPhone.
Perhaps the most important aspect of a modern smartphone, the operating system is where the battle between two devices is won or lost. Sony has made a few changes to Android for the Xperia Z, but nothing as extreme as Huawei's efforts with the P6, or even Samsung's TouchWiz.
Sony has installed its own wallpapers and lock screen, adjusted the application drawer and bundled its own apps and widgets - nothing too obtrusive or anything which would make the phone unstable.
In the other corner we have Apple's iOS 7, an all-new user interface which does away with the skeuomorphic design (torn pages in Calendar, green felt in Games Center) of all previous iOSs, replacing it with a clean, flat and colourful UI. It'll take Apple fans some getting used to, but the changes are logical and point the company in a new design direction which we expect to see spread across its product portfolio over the coming year.
Is one operating system better than the other? Impossible to say, but if there's a noticeable different it is that Android offers a more open and customisable experience, while iOS is more restrictive but with this comes a simpler, more intuitive system.
Just as it borrows technological knowhow from its Bravia TV range for smartphone screens, Sony can look to its Cybershot business for giving smartphones impressive cameras. The 13-megapixel sensor of the Xperia Z is something of a mixed bag, however.
In our review we found the Superior Auto mode to be excellent, adjusting all parameters automatically to take the best shot based on lighting and the environment you're in. But we found the resulting images to sometimes look too processed and overly-saturated; thankfully, shooting in manual mode fixes this, but you'll need a bit of photography knowledge to get the most out of it.
Over to the iPhone 5S, and we have an 8-megapixel rear camera with a dual flash (an improvement over the iPhone 5) and full HD video recording - and 720p can be recorded at up to 120 frames per second to make slow motion footage. iOS 7 brings a new camera interface, a range of new filters and the ability to shoot Instagram-style square photos.
Copying the HTC One, Apple has developed an image sensor that is not only 15% larger than the iPhone 5's, but also features larger pixels, capable of capturing more light and producing higher quality images in low-light environments.
With Apple, Samsung, Nokia and HTC for company, Sony still feels a bit like an outsider in the smartphone market, but with the Xperia Z it has proved how it can produce a competitive phone - and the new Xperia Z1 flagship will be along later this month, too.
Pitted against the iPhone 5S, the Xperia Z is a solid option, with comparable design and build quality - although they both lack the curved comfort of the HTC One - strong performance, and a smart, stable and unobtrusive take on Android. Choosing between the two will likely come down to brand loyality and which operating system the buyer prefers.
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