Sony has announced the Xperia Z2, a flagship Android smartphone with a 5.2in display, Ultra HD '4K' video recording, and the same waterproof design as its Z1 predecessor.

Unveiled at the company's press conference at Mobile World Congress in Barcelona, you would be forgiven for mistaking the Z2 for the Z1, which arrived just five months earlier. Both phones share the same metal chassis, sleek-yet-industrial design and waterproofing - but while the Z2 is evolution rather than revolution, it improves on every aspect where the previous model fell short.

"Details make the difference" is an appropriate tagline for the Xperia Z2, given it is a number of small changes which add up to make what promises to be a far more capable phone than the Z1 from late last year.

The Z2's screen is 0.2in larger, but the phone itself is lighter and with a footprint almost identical to that of the Z1; the new phone is fractionally taller, but overall its proportions are better, improving on the Z1 which always felt like it was larger than necessary.

At 1080 x 1920, the Z2's screen resolution is the same as before, but colour reproduction has been improved with a wider colour gamut, producing more shades from the green and red ends of the spectrum.

Ultra HD video

Around the back, Sony has kept the same 20.7-megapixel camera from the Z1, but now it offers Ultra HD (4K) video recording, as well as 120 frames per second slow-motion, and a range of new software features.

Sony Xperia Z2
The Z2\'s 20.7-megapixel camera can shoot 4K Ultra HD video. IBTimes UK

Ultra HD recording might sound unnecessary, given the high cost and limited choice of Ultra HD televisions currently for sale, but Sony says including the feature in the Z2 is the act of "future-proofing your memories," so you'll be able to play them in 4K sometime in the future.

Marketing speak perhaps, but the sooner more devices like this offer 4K, the sooner the price of compatible televisions will fall.

Another major camera enhancement is Steadyshot, which uses software to make your videos smoother. Sony demonstrated this by showing live video filmed by two Z2s on plates moving in a way to simulate running with your phone. As you'd expect from such an experiment, the Z2 with Steadyshot switched on produced smoother video.

There's also Timeshift burst, which takes 61 photographs in two seconds - one second before and one second after you press the shutter button - to help you pick the best image.

New camera gimmicks include being able to shoot video with augmented reality scenes, such as dinosaurs walking about in the foreground - if that floats your boat.

Speaking of boats, Sony has done little here to rock it; instead, the Z2 is a small upgrade to make the Z1 what it always should have been. Other than the slightly larger screen and thinner design, the Z2's biggest feature is its bundled earphones.

Sony Xperia Z2
The Sony Z2 will be available in black, white and purple when it goes on sale in March. IBTimes UK

Included with every Z2 sold (in the UK at least, Sony tells us), a pair of in-ear headphones make use of the Z2's built-in noise cancelling software - a smartphone world-first.

Where regular noise-cancelling headphones need their own batteries and processing hardware to block out the ambient noise of planes and trains, Sony's earphones borrow processing power from the phone itself. A microphone on the earbuds feeds ambient noise to the phone, which then cancels it out.

During a brief test we were impressed by the technology; the earphones blocked out the noise of city centre traffic (simulated by a loudspeaker nearby), but the sounds of car horns and other occasional noises still cut through, ensuring the technology doesn't leave you completely deaf to the outside world.

Unfortunately, the tech doesn't work with third-party earphones, but those provided by Sony are good enough for many buyers to consider using them instead of what they already own.

The Xperia Z2 goes on sale in late-March and will be priced roughly the same as the Z1, although we are waiting for Sony to announce a specific price.

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