(Pocket-lint) - The Huawei Mate series did big-screen before big-screen was even fashionable. Now that it's an increasing norm, the Mate 9 finds itself the focus of greater attention than its predecessors - and for good reason.

After all, the big phone market is in something of a spin: Samsung has crashed out with the Note 7, leaving Apple and Google to cruise along with the respective iPhone 7 Plus and Pixel XL phones. Both of which are just about as expensive as phones get, priced from £719 a piece.

As long-time Huawei Mate fans - we used the Mate 8 for months - we had waited with baited breath to see what the Mate 9's play would be. But unlike its predecessors it's not gone in with a low-blow price point to send the competition scuppering. Instead this £549 handset has nipped and tucked the screen into a 5.9-inch form (but stuck with just a 1080p resolution), ramped up its interior specification, and comes with a dual camera arrangement too.

With the price gap shrinking between the available big-screen options, however, and Huawei's latest EMUI 5.0 software rolling out with some overzealous app permissions handling, does it have the big features to stand apart from the competition?

5.9-inch 1920 x 1080 resolution display

156.9 x 78.9 x 7.9mm metal body, 190g

Available in white or silver (black front) in UK

At first glance the Mate 9 looks a whole lot like its Mate 8 predecessor from the front. The screen is 5.9-inches across diagonally (rather than the 6-inch of the Mate 8), which means the dimensions are the tiniest bit reduced - but only by a millimetre, so you really won't notice that in the hand.

It's only really when flipping the phone over to reveal its new dual camera make-up that the biggest differences can be seen, though. The new twin cameras - one sensor 12MP colour, the other a 20MP Leica-sourced black and white - are stacked vertically in a single protruding, optically-stabilised unit (so are different to the existing P9 model), with flash and laser autofocus positioned alongside.

So the Mate 9 is, in essence, a Mate 8S. Which is fine in one sense, because the full metal body with chamfered edges is well made. But in another sense it's not so fine, because Huawei did something very strange at the Mate 9's global launch: it showed off a special-edition Porsche Design model before its new supposed champion. Which has a 5.5-inch screen, curved edges and, despite its huge €1,395 price tag, looks and feels a lot better than the Mate 9 (and a whole lot like the Samsung Galaxy S7 edge, too).

Since then it seems our prediction of the Porsche Design version being used as the base for Huawei's next phone rings true. At CES 2017, the Chinese company unveiled the Mate 9 Pro: a China-only (for now) Huawei-branded version of the PD model.

Right now, however, we have to ignore those devices because the larger pocket-poker Mate 9 is the phone that's been living in our hands and alongside our leg for a number of months. Plus it is - finally - available in the UK, priced £549 via Three.

Kirin 960 chipset, octa-core (4x 2.4GHz, 4x1.8GHz)

Mali G71 MP8 GPU, Vulkan API

4GB RAM, 64GB on-board storage (plus microSD)

The Mate 9 does quick-strike with many points of merit. It's got 64GB on-board storage as standard. There's dual-SIM capability, or the second slot can be used for a microSD card to further expand that storage. It's got a great fingerprint scanner that's well positioned on the rear, too, and works as well as - if not better than - the nearest competition. And it's got up to Cat 12 4G LTE capabilities - meaning multiple bands for speedy wireless connectivity.

Now draw breath. But the biggest thing is the boost to its internal processing and graphical power. As the first device on the market to use the HiSilicon Kirin 960 chipset, with ARM-sourced cores, it's said to be 180 per cent more CPU capable than the earlier Mate 8. You wouldn't think it just looking at the numbers compared ot the 950, but the 960 is nippy.

From our point of view, though, it's the latest Mali G71 graphics that really sets the Mate 9 apart from other Huawei phones. Frequently we've bemoaned how games might have the occasional stutter or take a bit too long to load. With this ramped-up GPU on board the Mate 9 hasn't had any such troubles when running titles.

From Plants vs Zombies Heroes, to Candy Crush Saga and beyond. And while those might not sound like the most tasking of gaming apps, plenty of devices will stutter animations between completed levels, or when graphics slide in across the whole screen. Not so the Mate 9.

Which beds the device down well to take-on some of its pricier competition. The one that Huawei really has in its sights is the iPhone 7 Plus. Technically the Mate 9's GPU isn't as proficient as Apple's (even Huawei said this on stage at the Kirin launch in Shanghai), but the company claims the way it interacts with memory and storage makes it faster in almost all cases. We'll hand it to the company: the Mate 9 feels good in use and is consistently quick.

Android 7.0 with EMUI 5.0 skin

App twin for dual WhatsApp / Messenger

Knock Knock knuckle-based commands

There's always the "oh, by the way" software point to be made with Huawei though. The Mate 9 comes with Android 7.0 Nougat from launch, with the company's EMUI 5.0 re-skin over the top. By and large it looks and feels like a normal Android operating system, but with some tweaks that serve in both positive and negative ways.

Despite the phone telling us it's running EMUI 5.0, as it has been since day one, there have been a various patches to address some smaller issues in operation. The first of which was notification which used to show as an accumulative number to the top-left corner of the screen, but which now show as individual app alert icons.

This update has introduced a fairly considerable downside for us too: WhatsApp, with all possible permissions switched on, often goes to sleep in the background, failing to deliver any alerts. The only way to get these alerts is to openthe app itself and wait a few seconds. This never happened pre-update. Hopefully the next update will put this irritation right.

Some other parts are still a little scruffy too: the battery percentage and 24-hour clock indicators are in different fonts in the default theme. C'mon, details matter.

With such a big screen, Huawei has also implemented a system to avoid accidental touches doing things you don't want, such as firing the shutter in camera, for example. We've still managed to shoot pics by accident though. And the more we've used the phone, the more we've found this mode just doesn't work. Indeed, it can get in the way: we've seen it most come into play when one-handed holding the device and trying to type - the letter "p" tends to stick, not completing an ongoing word when using SwiftKey, as one example.

Then there's so-called Knock Knock, which is Huawei's knuckle-based control mechanism to make, say, screen grabs and audio recordings, or write on-screen letters with your knuckle to quick-launch an app. At first sight, back in the (then-called Ascend) P7 era, this tech was terrible and struggled to recognise the knocks. It's come a long way though - and now, if you remember to use it, it's quite practical. You can switch it on or off if it's too much to manage too.

On the positive side, EMUI 5.0 bakes in an App Twin feature that means typically device-locked applications - Facebook Messenger and WhatsApp for UK audiences - can be duplicated, one per SIM. So if you have a business account and a private account both can run simultaneously. It works well. And it's easy to switch off the second SIM if you don't want that part of your life/business active at a given time.

There are some additional apps that have throw themselves into the mix too: Huawei Health, which can track steps and fitness activities to help you achieve goals; HiCare which is a contact service with Huawei if you encounter device issues; HiGame, which, similar to Samsung's implementation, is a pointless secondary receptacle for gaming apps; and Todolist which, like the name says, is a to-do list.

We've also spotted various software features on the Mate 9 Pro - Student Mode, Trustspace being two examples - which we believe will make their way over to the standard Mate 9 as future updates roll out.

4,000mAh battery

USB-C charging

Average 16-hours life per charge

A trait of EMUI software is that it's really critical of battery life. And here's where the software, once again, goes a bit overboard. The app permissions are incredibly demanding by default, limiting all manner of alerts and notifications that you might want active.

Pop-up high-level battery use notifications are also commonplace (which happen per application), with repeat dismisses not baking into the phone's memory that you might actually want to see this app each and every time. You can go into permissions manually and make adjustments for individual apps about what they can and can't do - from drawing over other apps, through to closing down when the lock screen is activated - so in that sense there's good granular control, but it's not particularly consumer friendly by default.

Now, the earlier Mate 8's battery life was astoundingly good. The Mate 9 shares the same 4,000mAh cell, but, for a variety of reasons, we've not been getting quite as long a life from it. It'll easily serve a long day, though, we just wouldn't call it a full-on two-dayer. Saying that, after multiple weeks of use we tend to not fret about always plugging it in at night, because it lasts plenty long enough and offers fast-charging.

On average, we've been returning around 16-hours of use per charge, which is good going. Examples have differed, such as an office day when out and about - serving 13-hours of mixed use, with two long periods of screen off time. Over a weekend we saw around 21-hours of use from a single charge, with less work-related tasks easing off consumption. Switching off things like NFC and Bluetooth will assist, or cutting back on screen brightness by unchecking the auto-brightness box.

One point is that the latest EMUI 5.0 software is brighter, lighter, whiter. It might sound like a toothpaste ad, by ditching the complex colours and themes of earlier software to run with more bright whites, the screen is working harder more often.

NFC also seems to be highly impactful on battery life. The new Kirin processor is likely to be more taxing too - it's certainly run hot from time to time. And, of course, dual SIM use will also have an impact - although we haven't used two SIM cards for the duration of this review at all, because we don't run two in everyday life.

4.5V 5A SuperCharge fast-charging

Dynamic current adjustment based on source

Fortunately fast-charging - which Huawei calls SuperCharge - is on board the Mate 9. By lowering the voltage (to around 4.5V) and upping the current (to 5A) the battery can be charged in double-quick time - some 50 per cent quicker than the Mate 8 - meaning just 30-minutes at the plug could see the Mate 9 have almost 60 per cent charge. This all sounds very Qualcomm QuickCharge 4.0, albeit beating Qualcomm to the punch.

A potential problem here is safety given the increased voltage. We've all heard about Samsung Note 7 phones overheating and exploding into balls of fire. Huawei has put in a dynamic charging mechanism, meaning the Mate 9 can adapt to the source charger and cable used as required - so a shoddy third-party charger will make the phone dynamically lower the current (and slow down charging in the process, but that's fine). A five-gate protection system also checks different points throughout the phone to ensure it's not overheating. That's not to say the phone won't get hot, though, because it can.

One of the potential issues with the SuperCharge system is that higher voltage recharging systems are more likely to run down the battery's longevity. Although Huawei denies this will be the case with the battery, it also confirmed the underlying source battery is the same as that in the last-generation Mate 8. Sounds like something is amiss here for all that to add up - and after a couple of month's of use we have to say the longevity isn't as long-lasting as it was.

Intelligent algorithm to improve device longevity

Prioritises your favourite apps, based on use

One of Huawei's big claims about that Mate 9 is that it is born fast and will remain fast. We've only had the phone for a couple of months, so it's hard to judge how true this is and will be.

But here's the background on what the company has done. The new Kirin chipset has been designed to function with a new intelligent algorithm to learn your usage over time and prioritise the importance of apps and avoid slowdown. Before launch Huawei was calling this a very Apple-sounding "iAware" - a name that, unsurprisingly, has vanished from the official product release.

This technology is designed to get better over time for an improved life experience that doesn't slow down after a matter of months. Its trio of target areas - smart memory allocation, CPU allocation and storage optimisation - are the basis for its operation. The algorithm, which implements storage defragmentation, doesn't appear to exacerbate any of the pop-up notifications compared to earlier EMUI software. The only way to know for sure that it works is to fast-forward a year into the future or something.

Twin 27mm f/2.2 equivalent rear cameras

12MP colour and 20MP monochrome sensors

Optical image stabilisation

4K video (H.265 compression)

When Huawei launched the P9 smartphone its headline feature was a dual camera setup - one colour, one monochrome - with a Leica partnership. That relationship continues with the Mate 9, but the arrangement is slightly different.

The two sensors in the Mate 9 are different resolutions: the 12-megapixel full colour one is paired with a higher-resolution 20-megapixel monochrome module. Both peer through 27mm equivalent, f/2.2 aperture lenses, and both offer optical image stabilisation - hence the rear bump on the handset (which is kind of ironic, given how enthused Huawei CEO, Richard Yu, was when unveiling the "no bump" P9).

The Leica-partnered software is slightly updated compared to the P9, with a pinch-to-zoom feature that can digitally zoom into the frame. This is Huawei wanting to chase down the Apple iPhone 7 Plus, but without utilising two different lens focal lengths we're not convinced it's a particularly giant leap forward compared to the P9. It does offer a quirky feature though: the 20MP black and white image details can even be utilised by the colour camera to enhance the overall detail in the frame to deliver 20MP colour images. They're still way bigger than you'll need from a phone, though.

Whether you care about a dedicated monochrome sensor or not will come down to your way of thinking. We think proper black and white is fun but not essential, really. We have got some good results out of it.

The same can be said for the colour camera. Huawei wants to play with the big boys and this effort - while not the very best out there; the camera app is slower to load than the Google Pixel - is knocking on the door of the best flagships, for sure.

Focus is snappy and image processing is well handled. Low-light images don't go overboard with image noise, which is great news, while auto high dynamic range works well. If you want full control - in either colour or mono options - then a swipe up will unveil all the settings you could want.

But while the main camera elements are all good, we find some of the dual camera abilities just gimmicky. The ability to apply a fake bokeh down to f/0.95 in post is often overbearing and just looks plain weird.

We get that the cameras can map depth and offset these measurements for relatively convincing results - something Apple, HTC and others have played with (all unsuccessfully) - but it doesn't mean that you necessarily should. Use it subtly, for the right shot, and the fake depth-of-field effect can work. We're just not big fans.

How we feel about Mate 9's the cameras largely reflects how we felt about the P9: we think the monochrome sensor is fun, but a rare feature of genuine use; the core camera is handled really well, with point-and-shoot, manual options and even 4K video capture all ticking the boxes; and the post-processing options can sometimes work against what this flagship does so well at a core level.

Verdict What might come as a surprise about the Mate 9 is just how much it's like the Mate 8 - and we were expecting bigger changes, the kinds of changes we've only got to witness in the Mate 9 Pro and special edition Porsche Design models. Where the Mate 9 clearly differs from its Mate 8 predecessor is with its performance. The latest Kirin 960 processor and GPU runs applications smooth as butter. Battery performance from that 4,000mAh cell is strong for a guaranteed all-day experience and SuperCharge fast-charging is great. But that comes at the expense of the latest EMUI 5.0 software, which can being annoyingly persistent in its strict permissions, limited alerts and alt-Android ways. The Mate 9 also sees a price jump, which at £549 (via Three netowrk) is begining to know on the door of its Apple and Google competitors. It undercuts them slightly, plus delivers headline features such as a decent dual camera. But with that price gap now closing, the Pro/Porsche Design models casting a shadow of sorts, and few points of distinction to really set the Mate 9 apart, Huawei is largely banking on Samsung's explosive exit from this market to succeed.

£399 If it's affordable that you want then OnePlus rules above all. With a 5.5-inch screen, 64GB on-board storage and a whopping 6GB RAM you'd think this flagship specification would cost more. As an O2 exclusive (in the UK) it's easier to buy than ever before too. £719 The extra £70 or so you'll need to part with compared to the Mate 9 makes the Pixel XL worth it. The 5.5-inch Quad HD screen looks super-sharp and with Android Nougat (v7.1) on board from day one it's the most up-to-date and advanced Android phone going - no EMUI hiccups. No dual cameras to be found here, though, but with an exceptionally fluid experience it's a great phone. £719 If you're not determined to buy an Android phone then Apple's iPhone 7 Plus could be the perfect ticket. It's pricey, but not that much pricier than the Mate 9 all things considered. With a 5.5-inch screen, the iPhone might sound as though it's a smaller device, but the build actually makes it slightly wider in the hand. There's a twin camera setup present and correct, if that's a feature top of your wishlist. China only (£TBC) This is the Mate 9 that we would have liked all along. A Quad HD 5.5-inch screen, curved body and smaller frame than its Mate 9 cousin make for one attractive device that, well, looks a lot like the Samsung Galaxy S7 edge. Sadly this is China-only for the time being, but we're sure it'll end up in the UK in the future... it'd be mad to miss it out, no? Best smartphones 2020: The top mobile phones available to buy today

Writing by Mike Lowe.