What an upgrade: a gorgeous Quad-HD screen, vastly improved build quality, astonishing performance, more manageable software, even better photography performance... And yet, much of the debate surrounding the new Galaxy S6 goes something like this: "It looks like an , and just like Apple's phone it now has a non-removable battery, and no microSD support or waterproofing. Samsung's lost me as a customer."
But let's not get our knickers in a twist: the S6 gains so much more than what it loses. And we can quite easily live with what we're losing. Also see: .
The Samsung Galaxy S6 does indeed look a bit more iPhone than did the , but it's still Samsung through and through. Remember what we had before, with that awful dimpled plastic rear? It's no longer waterproof, but at least those who don't drop their phone in the loo needn't fiddle with that irritating plastic flap each time they need to charge their phone. For those of you who really need the waterproofing, look to the rumoured .
With 32-, 64- and 128GB storage options, OTG support, 100GB of free OneDrive space and unlimited Google Photos storage for your photos and video, is the lack of microSD really a problem? Storage has only ever really been a genuine issue when it comes to apps, which more often than not couldn't be moved to the SD card, and the Galaxy S6 now has at least double the amount of internal storage for these. You will likely find faster performance when accessing files stored on internal- rather than removable storage in any case. Also see: .

We won't fob you off with the excuse that reduced battery life can be countered with super-fast charging, built-in wireless (not-so-fast) charging and an ultra power saving mode that makes the phone pretty much unusable for all the things you want it for. The loss of 250mAh from the battery capacity and the addition of a higher-resolution screen is not the combination we were dreaming of.
But let's not pretend the Samsung Galaxy S5 would last a full working day for most users. Nor would most other high-end phones for that matter. So you used to have to carry a spare battery; now you need to carry a or use a battery case. And as you'll discover below, that's a compromise worth making. Also see: .
Samsung Galaxy S6 review: Price and UK availability
The Samsung Galaxy S6 is available to pre-order now from and all major UK mobile operators. SIM-free it costs £599 with 32GB of storage or £660 with 64GB, while pricing for a 128GB version is coming soon. The device will go on sale on 10 April 2015. Also see: .
Somewhat surprisingly, this means SIM-free the Samsung Galaxy S6 is actually more expensive than the , which costs £539 for the 16GB model, £619 for 64GB, and £699 for 128GB. Even on contract this is a pricey phone, so we recommend waiting a few months for the SIM-free price to drop - which it will, rapidly.
We got our review sample from , which is offering Wi-Fi calling on the Samsung Galaxy S6. For commuters or those travelling to remote areas, the ability to place calls over Wi-Fi when there's no cellular signal will be a real attraction. If this doesn't sound like something you would use, also look to other mobile operators to find the deal best suited to your needs. See all .

Samsung Galaxy S6 review: Design and build
It has to be said the S6 is the best-looking Samsung Galaxy yet, ditching the dimpled plastic rear cover of the in favour of a tough Gorilla Glass 4 back panel and metal chassis. At last Samsung's S-series flagship looks, feels and acts like the premium smartphone it is. (A phone well worth protecting - see .)
We weren't at all keen on the shiny mirror finish to the Blue Topaz model we saw at (read our original hands-on with the S6 on the next page), but our Black Sapphire sample is gorgeous. The Galaxy S6 is also available in White Pearl and Gold Platinum. It does attract fingerprints; more so with the coloured versions than the white and black models. Whichever one you choose, we highly recommend viewing it in store first.
Samsung has long been criticised for copying Apple's designs, and with the S6 you can understand where some of those claims might have come from. Indeed, Samsung has picked on all the things we hate about the iPhone, and produced a handset that will anger many S-series fans, removing the waterproofing protection and the ability to add in removable storage and replace the battery. (If you need more power to get you through the day your best bet is now to use a ).

In other respects the two are also similar, in the same way are all premium smartphones. More so when viewed side-on, with similarly rounded edges, button- and port positioning. For example, on the right side you'll find a power button and SIM slot, at the top left are volume buttons, and on the bottom a headphone jack, charging port and speaker grill. One might argue these are simply the best places for those things, of course: while we'd prefer to see a front-facing speaker, we wouldn't like the S6 to be any larger; it's already at the limit for comfortable one-handed use. Also see: .
The lines on the iPhone's rear that extend to its edges appear to be mimicked on the S6's sides, with plastic strips apparently used to allow signals to pass through the metal. Here, though, they are found at the top- and bottom edges rather than left- and right.
Flip over the Samsung Galaxy S6 and its camera is centred at the top of the device and protrudes much further than that of the iPhone 6, which sits at top left. Both phones will therefore rock when placed and prodded on the desk, but the central positioning and squarer design of the Galaxy's camera means it comes off better in this regard. Also see: .

Forget what you've read: the S6 is larger and thicker than the iPhone 6. Although Samsung quotes 6.8mm against Apple's 6.9mm, in our lab we measured 7.1mm. And taking into account the protruding rear camera, it's actually 8.7mm. At 138g, it's also 9g heavier than the iPhone 6.
The heart-rate scanner remains present and unique to Samsung, but now has the neat functionality of acting as a capture button for the selfie camera. This pairs with the preinstalled S Health app to help you keep track of your daily activity and goals. Also see: .
One thing Samsung has clearly borrowed from the iPhone 6 is its fingerprint scanner, and we're so glad it did. Now it works: first time; every time. Built into the home button as before, the S6 now uses touch- rather than swipe-style recognition, just like Apple's . It's easy to set up, and simple enough to use that you will actually want to do so. The fingerprint scanner will become more useful later this year when comes to the UK, too.

But we've saved the best until last here: the biggest difference between the Samsung Galaxy S6 and iPhone 6 is the Galaxy's gorgeous, super-high-resolution Quad-HD screen. With 2560x1440 pixels stretched across a 5.1in screen, the Samsung has a crazy pixel density of 577ppi - sharper even than the . You might argue that such a high-resolution panel isn't necessary on a device of this size - particularly one that you want to keep going all day long - but it's simply stunning, and games, videos and pictures look amazing. Also see: .
Samsung uses Super AMOLED screen technology in its mobile devices, which omits a backlight and therefore places less of a strain on the battery. That's not to say this screen is dull - at 600cd/m2 it's an improvement over the S5 and easy to see even in bright daylight. sAMOLED panels typically produce deep contrast (dark blacks and crisp whites) and saturated colours - an effect you'll either love or hate, and we love it. Also see: .
Samsung Galaxy S6 review: Hardware and performance
Something that's instantly obvious when you pick up the Galaxy S6 is just how fast it is, with the only lag we could find occuring when trying to use the multi-tasking screen or swiping in the Flipboard pane to the left of the home screen (we removed this in any case). Everything else is fluid and achieved in an instant - even browsing the web on the train in notoriously patchy areas, we couldn't believe our eyes as pages that would usually take several seconds to load were just there (yes, even PC Advisor).
There is less bloatware dragging down this phone, and TouchWiz really does feel as though it's had a rocket up its bum. (We'll talk more about software later on.) But the core hardware is impressive, too.
Having shunned the Qualcomm Snapdragon 810 chip originally expected to be found inside the UK version of the Samsung Galaxy S6, the company has opted for its own octa-core Exynos 7420 processor. This is a 14nm, 64-bit chip built with two quad-core (1.5GHz Cortex-A53 and 2.1GHz Cortex A-57) sets. A Mali-T760 GPU is integrated, and there's 3GB of LPDDR4 RAM.
Storage-wise you get a choice: 32-, 64- or 128GB, plus unlimited storage for standard-size photos and video via Google Photos (see ), and 100GB of free OneDrive space. After installing a handful of benchmarking apps on our 32GB review sample we had just over 22GB free.

Oddly, given the identical hardware inside, the Samsung Galaxy S6 didn't fare as well as the in our benchmarks, but that just goes to show how reliable are such tests. Nevertheless, both phones turned in a significantly higher multi-core result in Geekbench 3.0 than anything we've ever seen before, with the S6 recording 4438 points and the Edge 5076. Their closest competitor here is the , with 3778 points. In single-core performance the phones turned in 1347- and 1501 points respectively. Also see: .
SunSpider performance is really very good for an Android phone, with the Samsung Galaxy S6 recording a tiny 462ms (this is iPhone territory) when tested with the preinstalled Samsung browser. However, for a fair test we run all our SunSpider tests in , in which the S6 recorded 1048ms. Again, the S6 Edge fared better, with 990ms (lower is better in this test).
For graphics benchmarks we use GFXBench 3.0, in which the Samsung Galaxy S6 recorded 30- and 14fps in the onscreen elements of T-Rex and Manhattan. In the newly released Manhattan 3.1 test the S6 scored 6fps.
We did find the Samsung Galaxy S6 became rather warm in use (and not only when stressing the hardware with our benchmarks), but not uncomfortably so.
Inside the Samsung Galaxy S6 is a 2550mAh battery, slightly smaller than the 2600mAh battery inside the Galaxy S6 Edge. However, in our Geekbench 3.0 battery life tests it performed better. The Galaxy S6 managed 6 hours 53 minutes in this test, with a battery life score of 4136. Meanwhile, the Edge recorded 6 hours 41 minutes with 4011 points.
There are a couple of other points worth making in terms of the battery, too. You might lose 250mAh on the battery capacity, the ability to swap in a spare and gain what's likely a power-draining screen, but the S6 features wireless charging as standard (both PMA and Qi standards), and also supports quick charging. Samsung says you'll get enough power for four hours use in 10 minutes, and that it'll charge in half the time of the iPhone 6. With the supplied adaptor we got from zero to 40 percent in 30 minutes.
We're in the process of battery testing our Samsung Galaxy S5 to see how the battery life compares between S5 and S6. Unfortunately, our S5 is now a year old and it's possible that the battery has degraded. Nonetheless it should make interesting reading. We'll update this article as soon as the results are in. Also see: .
Let's not forget the Samsung Galaxy S6 also has an Ultra power saving mode, which turns off non-essential features and screen colours to vastly increase battery life, although it may well make your phone unusable for all the things you want it for.

Samsung Galaxy S6 review: Connectivity
Connectivity options are strong on the Samsung Galaxy S6, with everything you'd expect: dual-band 802.11ac Wi-Fi, Bluetooth 4.1, , an IR blaster and a Download Booster that can pair the power of Cat 6 LTE with Wi-Fi for downloads over 30MB. The Samsung Galaxy S6 takes a single nano-SIM. Also see: .
Samsung Galaxy S6 review: Cameras
As a cameraphone the Samsung Galaxy S6 is excellent. As before there is a 16Mp camera with LED flash at the rear, but it now supports smart optical image stabilisation, automatic real-time HDR and IR Detect White Balance. There are all the manual controls and camera presets you would ever have need for, and we particularly like the fact a double-tap of the home button can launch the camera in a fraction of a second.
With very little photographical expertise, we found the S6 fast to focus and able to take great shots out of the box - even in low light. There's no dedicated capture button, but in landscape mode either of the volume buttons do the job. You can see the quality of the camera in our standard St Pancras test shot below.

Video is supported up to 4K, although set to full-HD by default. This makes sense since it would otherwise eat through your storage. The S6 also has slow- and fast-motion video modes.
At the front of the phone is a 5Mp selfie camera and, as we mentioned earlier, we like the ability to use the heart-rate sensor as a capture button.
Samsung Galaxy S6 review: Software
So much of the Samsung Galaxy S6's software was hyped up before its launch. Most importantly, TouchWiz was said to be stripped right back, and not as laggy with less bloat preinstalled.
There are fewer apps preinstalled on the S6, but you still get a lot. As well as all Google's apps you get Samsung's own apps for browsing the web, listening to music and watching videos, managing emails and calendar appointments, plus social apps for Instagram, Facebook and Messenger, and several tools including Memo, My Files, S Voice, Smart manager, Voice Recorder and Smart Remote. Then there's the Galaxy Apps store, S Health and My Galaxy, as well as the rumoured Microsoft suite that turned out simply to be OneNote, OneDrive and Skype (you can always download Word, PowerPoint and Excel free from Google Play if you need them).
With our phone supplied by EE, we also found MyEE, Lookout and a Games & Apps store. So that's three app stores you'll find on this phone if you purchase it from EE.

What's different here is that although you can't uninstall many of the preinstalled apps, you can disable them or hide them from view. Plus, TouchWiz is fast.

The most notable changes TouchWiz makes to the standard Android 5.0 Lollipop OS installed on the Samsung Galaxy S6 are in the Settings menu and drop-down notification bar. Both are easy to find your way around and customisable, allowing you to choose which settings or toggles you want to access most frequently and place those at the top of the window. Also in the notification bar you'll find a brightness slider and shortcuts to S Finder and Quick Connect.

Some users will find TouchWiz's Easy mode beneficial, putting the phone's key features right at their fingertips. The Samsung Galaxy S6 also features a Private mode and Do not disturb, the latter preventing incoming calls, text messages and emails if you're trying to watch a film or play a game. Of course, if you still don't like it you can .

New to the Samsung Galaxy S6 are themes. Installed on the phone are the default-, pink- and space themes, and there's access to a new Themes store that offers free themes for everything from Hello Kitty to Lego.

Several gestures are supported. Besides those we've already mentioned, Smart Stay lets the Galaxy S6 track when you are looking at the screen and prevent it going to sleep. It also supports Direct Call (instantly calling a contact as you hold it to your ear), Smart Alert (vibrating when you pick it up to warn of missed calls or notifications), and gestures for muting the phone or taking a screenshot with a swipe of the palm.

One of our favourite software features of the Samsung Galaxy S6 is Split Screen, which lets you view two apps on screen at once. This is accessed via the multi-tasking menu, but doesn't support every app on the phone.

The Samsung Galaxy S6 also supports lock screen notifications, although these can be turned off in the Settings menu.
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NEXT PAGE: Our original hands-on with the Samsung Galaxy S6 by Ashleigh Allsopp.