At IFA 2015 Sony announced a trio of new smartphones which make up the Xperia Z5 range. As well and the Compact and Premium versions, the regular Xperia Z5 is here and this is our full and in-depth review. See: The best phones of 2015.

Also see: Best Black Friday Phone Deals

Updated 18 January 2016 with audio tests, then 29 April 2016 with new camera tests.

With technology in smartphones hitting something of a ceiling, it's hard to differentiate in a crowded and fierce market. Sony, like HTC and others, is finding it hard to compete with the likes of Samsung and Apple but will hope that the new Xperia Z5 will give it a needed boost.

Sony Xperia Z5 review: Release date and price

The Xperia Z5's official price is £549 if you go to the web store. although Sony has now discounted it to £469. However, you're probably better off going elsewhere as prices range from £325 from websites we wouldn't necessarily recommend, through to £399 from Debenhams.

Of course, its rivals have also dropped in price, and there are now plenty of new ones to compete with, such as the Huawei P9 and Xiaomi Mi 5.

If you want a smaller phone, the Z5 Compact is a cheaper option and has many of the same features. Also see: Best MiFi 2016.

Sony Xperia Z5 review: Design and build

In terms of design, Sony hasn't really changed its formula which has been in place since the original Xperia Z. The Xperia Z5 has that square industrial style look and feel which makes it instantly recognisable as a Sony handset. That said, there are some tweaks which are nice.

The Xperia Z5 looks more desirable than previous models if you ask us and this is largely due to the new frosted glass rear cover which give it a really nice matt finish and the graded metal frame which matches the colour you choose. You'll be able to choose from white, gold, graphite black and green with the latter being our favourite.

Once again, Sony offers full waterproofing and there's only one flap to cover the card slots so you don't need to faff around with headphone or USB ports which makes things hassle-free.Update: Sony has backtracked on the 'fully waterproof' claim and now says you shouldn't immerse the Z5 or try to take photos or videos underwater. Its website says "Remember not to use the device underwater. If you accidentally get the device wet with non-fresh water, wash the device with tap water."

A change you may have noticed is that the iconic round power button is gone. This has been replaced by a flat and slightly recessed button which also houses a fingerprint scanner (we'll talk about this more below).

Something we don't like, although it's a small detail, is that the volume rocker is now further down on the side of the phone. It's pretty close to the bottom and is quite difficult to use – above the power button seems to make more sense.

Unfortunately, the device has got thicker and heavier compared with the previous model. It's now 7.3mm and 154g compared to 6.9mm and 144g. Although that's not a big difference, the Z5 doesn't feel as nice in the hand compared to rivals. The square shape just isn't as ergonomic and there are places where the edge of the glass or metal is quite sharp.

This might seem like a small thing to point out but in day to day life it matters more than say a few extra frames per second in a graphics benchmark.

Sony Xperia Z5 review: Hardware and specs

Let's get a couple of things out of the way on the specs side of things. The Xperia Z5 still has a 5.2in screen with a Full HD resolution so that's the same as the Xperia Z2. The new screen tech is found on the Xperia Z5 Premium, which is the first 4K smartphone we've seen - we'll debate whether you need that over on that review.

The quality is still good but we would have preferred it if the regular Z5 was Quad HD. The only new thing to talk about here is that the display can be used normally even when covered in water droplets.

Another thing which remains the same is that the Xperia Z5 has a Snapdragon 810 processor, not the 820 as per some rumours. We found the phone extremely nippy in use, even launching the camera and in normal use it doesn't overheat quite like the Z3+.

However, it can if you push it hard enough. When recording 4K video we got a warning at around 19 and a half minutes - an icon notifies you of the high temperature, too - but we did reach 30 minutes of continuous recording without the camera switching itself off.

Sony Xperia Z5 review: benchmarks and battery life

Benchmark results are good, outpacing its predecessor and keeping up with rivals across the board.

4GB of RAM was rumoured but it remains at 3GB and there's 32GB (21GB available on our sample) of internal storage plus a Micro-SD card slot which can accept up to 200GB more, according to Sony. It's good to see Sony sticking with expandable storage with so many devices (the OnePlus 2, iPhone 6 and Galaxy S6 to name just three) not having this feature.

The Xperia range has long touted good battery life and the Z5 is no different with Sony still claiming two days of usage. The still non-removable battery is 2900mAh in capacity which is oddly 30mAh lower than the Z3+. You'll be able to quick charge the phone getting five and half hours usage from a 10 minute charge – however, the QCH10 charger is not included in the box and will cost you £19 from Sony.

In our battery benchmark test using Geekbench 3, we recorded a time of five hours and 37 minutes with a score of 3376. This is respectable but just over an hour short of rivals like the Galaxy S6 which we didn't expect due to the lower resolution screen. We have found battery life to be good from a user point of view and should last most the advertised two days.

So what has changed? Well Sony is going big on two features: the new camera and the fingerprint sensor.

Sony admits that it's a bit late with a fingerprint sensor but it's managed to do something a bit different. Yes, it's inside a button like rivals but the firm has put it inside the power button. This is firstly impressive since it sits on the side and is really slim but also means it's a much more ergonomic placement – exactly where your thumb naturally falls when you pick up the phone so all you need to do is push the power button and the sensor reads your print at the same time. It's consistently quick and accurate.

Sony Xperia Z5 review: camera review

Now onto the camera which is new for the first time since the Xperia Z1. The Xperia Z5 now boasts a 23Mp main camera (1/2.3in and f/2 aperture) with various improvements and features – it's the same camera on the Compact and Premium models, too.

Before we get to the bad news, we'd like to give Sony a nice round of applause for keeping the two-stage dedicated physical camera button on the side which not only launches the camera app whenever you need, but also makes taking photos easier and nicer.

Sony is touting three main improvements for the camera. It has the fastest autofocus according to the firm at 0.03 seconds thanks to a hybrid system, it also has x5 Clear Image Zoom which is meant to give better results when you zoom in on an object (or crop a photo) and it also provides the clearest low light performance.

However, we're unconvinced that the sensor really does have 23 million pixels. For one thing, Sony sets the camera to 8Mp by default so you'll have to head into the settings to switch to the full 23Mp compliment (this is a 4:3 aspect ratio). The second is that when you compare photos with rivals at 1:1, you see much more detail from those with 12- and 16Mp sensors, adding weight to the argument that it's really an 8Mp sensor that interpolates to 23Mp. Whichever is true, the photos speak for themselves.

Going back to what Sony says about the camera and that autofocus is incredibly fast. Perhaps not 0.03 seconds every time (that's pretty hard to measure) but it's one of the quickest we've ever seen and should help you to capture moments better when the window of opportunity is small. Focus is sometimes soft round the edge of photos.

The Clear Image Zoom feature seems to be nothing more than marketing hype as we've not found it to be at all effective. In fact, a photo taken at 'x5' compared to zooming in on a full-frame still is actually better. As usual, you'll want a camera with optical zoom if you want good results in this respect.

To illustrate this, here's a "23Mp" photo taken on the Z5. It's not too bad apart from the blow-out highlights.

Now let's zoom in 1:1 so you can see the actual detail.

Below is the same 1:1 portion from the Google Nexus 6P which has only a 12Mp sensor: it's sharper and certainly doesn't lack any detail compared to the Sony which, theoretically, has almost twice the number of pixels.

Low light performance is good but the Z5 lacks optical image stabilisation which plays a big part in preventing shots in poor conditions ending up a blurry mess. For most users, the camera will provide excellent photos and video using Superior Auto Mode and there a load of other camera apps to play with including Manual, Multi Camera and the slightly odd AR Mask which lets you have the face of a gorilla or even one of your mates.

The lack of stabilisation also affects video. Here's a 4K clip:

Overall the Z5 camera is very good but while DxO ranks it as the best in the world, we wouldn't go that far. It's not terrible, but there are much better phone cameras. To see a side-by-side comparison with the latest phones, including the LG G5, HTC 10, Galaxy S7 and more, see our best camera phone group test.

Sony Xperia Z5 review: Audio

Speaker Quality

It is a pleasant surprise to see the Xperia Z5 equipped with dual front-facing speakers. What makes the Xperia Z5 standout from the crowd is how concealed the two speakers are within the phone, where at first glance it even seems as if the speakers don’t even exist. However, this does come at a price: When the phone is used at maximum volume, the phone’s speakers create quite a lot of vibrations that are noticeable through the full metal body. In terms of loudness, it scored a 7/10 in our tests – as a comparison the Google Nexus 6P scored 9.5/10 with its dual front-facing speakers. Read more: Best Sounding Phones of 2016.

The sound quality of the speakers is decent, where the mids and highs are really well presented and bring out a clear natural tone to music. Furthermore, the overall soundstage and instrument separation is top-class, making us enjoy our music content even more. However the Xperia Z5’s speaker did fall short on the bass department, where the bass did not extend nor had any impact, which left us wanting for more.

Internal Sound Quality

The Sony Xperia Z5 uses the Qualcomm MSM8994 Snapdragon 810 processor, where we presume Sony is utilising Qualcomm’s WCD9330 Audio Codec to produce its audio. We found its sound signature to have an emphasis on the mids and highs, where the mids sounded a little boosted and the highs created a great sparkle. The same couldn’t be said about its bass response which left us disappointed; a lack of extension in the sub-bass and uncontrolled mid-bass let down the overall sound quality of the Xperia Z5.

In terms of loudness we had to use the phone at 75-80% volume which is louder than some of the smartphones we have previously reviewed. Read our in-depth smartphone audio comparison: Best Sounding Phones of 2016.

During our tests we found the phone to produce slight crackling and popping noises when used alongside an amplifier; for example, a car’s amplifier. We also noticed a pulse sound that occurred after the phone was connected via a 3.5mm auxiliary input.

Sony Xperia Z5 review: Software and apps

Sony hasn't done much on the software side with the Z5 range - it's really all about the design and hardware.

The Z5 ships with 5.1 Lollipop and Sony will, of course, make Android 6.0 Marshmallow available for the Z5 range but there's no timing for the upgrade at the time of writing. LG is rolling it out to the G4 starting week of 19 October which is very quick so we hope Sony can follow suit.

On top of the stock Android elements like recent apps, Sony still adds its floating widgets giving you things like a calculator, timer and even a web browser which can be resized, and pinned to the side when not in use. We also welcome the ability to customise the quick settings so you can make sure the ones you use the most are there.

We're seeing much less fragmentation with Android these days and Sony is one smartphone maker which doesn't really mess too much with the vanilla interface. It does have the firm's usual style and add-ons such as nice wallpapers, widgets and apps such as Walkman and PlayStation.

All of which are welcome but there are a bunch of other things pre-loaded such as Dropbox, Facebook, Amazon Shopping, Kobo Books, Vine, Spotify and AVG which we're not so keen on. We think users should be the ones to decide which apps are installed. Combine, they take up a reasonable amount of space but you can uninstall any you don't wish to keep which means this isn't a big problem.