By Will Goodbody, Science & Technology Correspondent
Sony continues to grapple with its mobile strategy in an effort to figure out what's the best variety of devices for it to sell and what segments to aim them at.
But for now it continues to churn out new flagship handsets, the latest being the XZ Premium – a smartphone that is right up there among the best available.
Out of the box, the XZ Premium I was lent for the purpose of this review looked like a stunning device.
The glinting "Luminous Chrome" metal and glass combo screamed premium.
But the gloss quickly came off when I started to handle it - the shining finish quickly became a fingerprint magnet all over.
That’s a pity because it is a lovely looking handset.
The other thing I would be concerned about it is how vulnerable the Gorilla Glass back on the handset would be if dropped while unprotected.
Sony has kept the angular feel to the phone, opting for square corners and only slightly rounded edges.
While the handset looks and feels bigger than most, the size of the screen isn’t so enormous because of large bezels around the edges.
The power button is on the side of the device, with the pretty accurate and fast fingerprint sensor built into it.
Just above it is the volume rocker, while on the base is a USB Type-C charging socket.
Sony has resisted the temptation to ditch the 3.5mm audio jack and it is placed on the top of the device.
The main camera lens on the rear is flush, as is the auto-focus and flash module.
Despite the fingermark issues, the XZ Premium does look and feel the part.
Sony has opted for a 4k display on the device, a definite unique selling point.
When playing 4k content the screen is superb, the clarity, definition, colours and contrast all top notch.
At 5.46 inches in size there’s just about enough real estate to watch that 4k content on, although it is starting to look on the smaller size against the enormous screen on the market leading Galaxy S8.
Finding material you want to watch in the extremely high resolution format can still be an issue.
But it’s not just video that is displayed in 4k – all the native content on the phone, from apps to the home screen is presented in the format too.
For some it will be a game changer, for others an unnecessary waste of money.
Few will argue with the quality though.
With the latest Snapdragon 835 octa-core processor and 4GB on board, the XZ Premium doesn’t lack power.
Apps open without any hesitation, as does the camera.
It will handle even heavy duty applications, games and multi-tasking with ease.
It comes with 64GB of in-built memory, but the microSD slot supports expanded memory of up to 256GB.
The handset has front facing speakers which pump out plenty of volume with pretty good quality.
We couldn’t judge the audio quality from the in-box headphones because we didn’t get any.
But it does support High-Resolution audio if you are a connoisseur of high quality sound.
The smartphone carries a 3,230mAh battery, which doesn’t sound huge.
But coupled with power management features and the latest chip architecture, it easily lasts through a full day of normal calling, texting, social media use and multimedia consumption.
And if you do need to top up, the phone supports Qualcomm Quick Charge 3.0.
The big new feature on the Xperia XZ Premium’s main camera is super-slow motion – the ability to capture video at up to 960fps.
That’s nearly four times more frames than most other competing phones and the result can be spectacular footage if you time it right.
There are different ways of capturing the video at this speed and I found it a little tricky to figure out how it all worked, although it is fun when you master it.
It’s a toy, however, and not one you are likely to use every day.
The good news, though, is that the main camera which you are likely to use regularly is also very good.
It’s a 19MP sensor with a range of different added features like electronic image stabilisation, HDR and laser autofocus to name a few.
There’s manual mode if you want complete control as well as full auto.
And a range of camera apps, including AR effect, Creative effect and 4k video.
Overall the quality is very strong. The camera is quick and accurate, the images it produces are generally good.
The quality of video it captures is also really good, although I found at times it struggled a little with low-light.
The front facing camera is a more than respectable 13MP sensor with SteadyShot.
It does what’s expected of it and I liked the feature which enables you to trigger the shutter by showing your open palm to the lens.
It being a Sony, the handset can be used for PS4 remote play.
It is also IP68 rated which means it is dust and waterproof up to 1m.
One aspect which is mildly irritating is the SIM tray, which is buried deep inside the slot where the microSDXC card is inserted.
There surely is a better way.
It runs on Android Nougat (7.1) and the Sony user interface is crisp, clean and easy to navigate.
Overall the Sony Xperia XZ Premium is a very good smartphone.
Some people seem to think its look is outdated, although I think it is a good thing that its style differs from the general trend towards curved and bezel-less screens.
It is a fingerprint magnet though which isn’t terrific.
The screen is superb when used with 4k content and the camera is good too.
Overall it is packed with features to make it stand out from the crowd, which includes the iPhone 7 Plus, Samsung Galaxy S8+, LG G6, Huawei P10 Plus and the HTC U11.
It won’t appeal to everyone.
But anyone with an open mind, deep pockets (it can be pre-ordered on pre-pay SIM free from Vodafone at €699) and who is a fan of Sony mobile devices are likely to be impressed.
Comments welcome via Twitter to @willgoodbody
(Update 1/6/17: Sony has been in touch to say the Xperia XZ Premium will be available from June 2nd through eir, Meteor, Vodafone and Carphone Warehouse. It will be available in Luminous Chrome, available exclusively with eir and Deepsea Black, available on all networks.)