Editors' note (March 28, 2017): Samsung has unveiled the Galaxy S8 and Galaxy S8 Plus, the follow ups to 2016's excellent Galaxy S7 and S7 Edge. Priced at $750 (£689 and AU$1,199), the Galaxy S8 features a beautifully curved 5.8-inch screen with an ultra-narrow bezel; facial recognition as an alternative way to unlock the phone; and Samsung's nascent Bixby voice assistant. The S8 Plus costs a bit more -- $850, £779 or AU$1349 -- and comes equipped with a larger body and battery, but is otherwise identical.

Samsung has instituted an eight-point battery test on its new phones in an effort to reassure customers that it has addressed the issues that plagued its exploding Note 7 last year. To see how the Galaxy S8 and S8 Edge stack up against their predecessors, check out CNET's side-by-side comparison.

Note: In April 2015, CNET designated the Galaxy S6 an Editors' Choice Award winner, but lowered the rating to account for the better features and faster performance of the Galaxy S7. The original Samsung Galaxy S6 review, published in March 2015 and updated since then, follows.

The Galaxy S6 leaves much of its Galaxy S5 DNA behind. Perhaps even more shocking than this materials about-face are the decisions to seal in the battery and leave out a microSD card slot, both choices made in service to staying slim. These are commonplace omissions in the smartphone sphere, but Samsung has been a die-hard defendant of both the removable battery and the extra storage option, until now. It's a move that makes a difference, too, at least on the power front. The S6's ticker ran down faster than last year's S5 did on a single charge.

In many ways, Samsung had no choice but to adopt this svelte, metal chassis and a pared-down, less "bloated" variation of Android 5.0 Lollipop. (Note that in February 2016 Samsung begun to roll out Android 6.01 Marshmallow to the Galaxy S6, bringing with it a number of new features including Google Now on Tap, "doze" mode for automatic extended battery life, support for Android Pay and more.) These moves silence customer complaints about the Galaxy S5's (and the S4's and S3's) plasticky build, while also girding Samsung against staggering iPhone profits and an army of decent low-cost rivals from Lenovo, Xiaomi and Huawei.

Luckily for Samsung, the S6 is good enough to win back straying fans while also surpassing the all-metal HTC One M9 in extra features, battery life and camera quality.

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On top of that, Samsung's S6 follows Apple's mobile payments lead with Samsung Pay, and takes a chance on its sturdy and home-made Exynos processor (versus the Qualcomm Snapdragon 810 that will be found in most of its high-end Android rivals). The S6 also bakes in wireless charging support and compatibility with a new version of the Gear VR virtual-reality accessory -- two features you won't find on any iPhone.

Does the new phone have enough in the way of looks and specs to reverse Samsung's sagging smartphone sales? Without a doubt. Samsung continues to build on its camera strengths while also offering interesting extras its Android rivals don't have. The only real danger is in longtime fans of microSD cards and removable batteries punishing Samsung by finding vendors that do. Samsung's hardware has long stood up to the iPhone; at long last, its physical design does, too.

Galaxy S6 and S6 Edge: Two devices, one family

If straight-sided phones are too vanilla for your tastes, check out my review of Samsung's Galaxy S6 Edge and its wraparound display. While the two share nearly identical specs, the Edge kicks the S6's premium feel up a notch.

Design: Metal and glass; plastic be damned

With a matte aluminum alloy frame and Gorilla Glass 4 on the front and back, the S6 lives worlds apart from the plastic construction of five generations of Galaxy flagships. It's obvious that this is a different beast, and one for which fans have been crying out for years.

Samsung didn't get here overnight. It built on the metal-framed Note 4 and more midrange Galaxy Alpha, before experimenting with all-metal chassis in the youth-focused Galaxy A5 and A3.

So, let's talk about this silhouette. The S6 has Samsung's familiar pill shape, with rounded tops and bottoms and straighter sides. The power button and nano-SIM card slot sit on the right spine. A micro-USB charging port and headset jack live on the bottom, and the left spine houses separate up-and-down volume buttons, just like the iPhone 6.

Now playing: Watch this: A fingerprint trick on the Galaxy S6 and S6 Edge

A central, metal-ringed home button joins two capacitive keys for calling up recent apps and paging back. A terrific new feature lets you double-tap the home button to launch the camera at any time, even when the phone is locked (though that takes a little longer). Samsung has also improved the fingerprint scanner, which you can use to securely unlock the phone; instead of dragging your digit down across a sensor, you now just rest it on the home button. It's fast and reliable on the whole.

On the back, you'll find the 16-megapixel camera (same as the Note 4), and a sensor array that includes the camera's LED flash and heart-rate monitor. Up top, the IR blaster beams out infrared for folks who want to use their phones as a TV remote.

A few niggly negatives: the camera protrudes a bit from the back, which some may not like, and the phone's glass surfaces become a smudge gallery for your finest fingerprints. And unlike the S5, the S6 isn't waterproof.

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In-hand feel

The Galaxy S6 feels far more fluid and thin than it looks in photos, especially compared with the slightly chunkier Galaxy S5. Next to its designer cousin, it's the S6 Edge that feels much slimmer than the S6, despite its being a hair thicker at its chubbiest point.

Samsung Galaxy S6, S6 Edge dimensions Galaxy S6 Galaxy S6 Edge Dimensions (inches) 5.6 x 2.8 x 0.27 5.6 x 2.8 x 0.28 Dimensions (millimeters) 143.4 x 70.5 x 6.8 142.1 x 70.1 x 7.0 Weight (ounces) 4.9 4.6 Weight (grams) 138 132

Because of its straight edges, the S6 isn't as smooth or seamless as the iPhone 6 with its rounded sides, but without a case, the S6 is easier of the two to grip. Keep in mind that the 4.7-inch iPhone 6 is also smaller all-around than the 5.1-inch S6.

While we're on the topic, the S6 looks too much like the iPhone 6 to ignore. Its footprint may be larger and it sides might be straighter, but the shape and placement of things like the headset jack, speaker grille and volume buttons are shockingly similar when you see two devices side by side. Even the color of the white phones is matchy-matchy, with nearly indistinguishable shades of matte silver trim.

Notably, the S6 packaging includes tear drop-shaped in-ear headphones that look like the next evolution in the iPhone's Apple EarPods.

Some color, lots of flash

Although the colors are fairly staid -- both models comes in platinum gold in addition to sapphire black and white pearl -- Samsung injects shots of color into the lineup with topaz blue, which is really pretty if it catches the light, and just looks black or generically dark if it doesn't. (The S6 Edge, meanwhile, tries on emerald green.)

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The incredibly reflective rear surface flashes color and throws back light. Samsung says this is to add depth and warmth, but the skeptic in me notes that relentless reflectance gets annoying to look at. (The white version minimizes this effect, but it's still apparent outdoors.)

Display so crisp it hurts

Even though Samsung hasn't bumped up the screen's 5.1-inch size, it has spiked the resolution of its AMOLED display to 2,560x1,440 pixels, a density of 577 pixels per inch (ppi), currently the best on the market. Now come the inevitable questions: can the human eye really appreciate detail that fine, and is the higher resolution worth the likely impact on battery life?

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The answer -- predictably, unsatisfyingly -- is yes and no. I grabbed an extra pair of eyeballs and placed the S6 side-by-side with the iPhone 6 (326ppi), Note Edge (525ppi) and Sony Xperia Z3 (424ppi). After staring at streaming videos, zoomed-in text and HD wallpaper, the S6 edged the rest only when we squinted really, really, really hard.

The S6's screen quality prowess was most apparent against the (poorer) Xperia Z3 in streaming video clarity and saturation, and less so against the iPhone 6. The Note Edge, which shares a 1440p resolution on a larger screen, came the closest to the S6 in terms of flawlessness.

Ironically, some of the revamped icons on the S6 home page look less focused, though every other graphic is razor-sharp.

If you plan on using the S6 in its Gear VR accessory -- which turns it into an Oculus Rift-style virtual reality helmet -- the extra resolution should really pay off because the S6 will be only a couple of inches from your eyes.

But in normal everyday use, the S6's nosebleed-high screen pixel density is probably too exact for most eyes to notice; it's an imposing feature on paper, but less critical in real life.

Softer software

In advance of the March 2016 rollout of the Samsung Galaxy S7, Samsung pushed Android 6.0 Marshmallow to Galaxy S6 users. Android 6.0 Marshmallow includes new features including Google Now on Tap, "doze" mode for automatic extended battery life, support for Android Pay and more. Read more about Android 6.0 Marshmallow here.

For years, customers have bemoaned the thick, heavy TouchWiz interface that Samsung uses as its custom layer over Android. No longer. Samsung's take on Android 5.0 Lollipop scales back its own additions and leans heavily on Google's Material design. Samsung succeeds in embracing a simpler layout without shedding all the software it's built over the years, though Android deserves much of that credit for providing the framework.

Screenshot by Jessica Dolcourt/CNET

The setup process is a lot smoother, thanks to Lollipop, with tutorials to help you turn on features (like S Voice and fingerprint scanning) along the way.

I usually make new phones completely silent, since chirps and haptic vibrations annoy me, but Samsung toned both down to acceptable Windows Phone levels.

Samsung has also whittled down the menus. Multiwindow mode, for split-screen viewing, still lets you open two programs at once, but instead of toggling it on yourself and selecting from a pop-out menu, it's always on and launchable from the Recents tray. You can still drag and resize these windows, even turning them into floating bubbles, like in the Note 4.

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Other mainstays include private mode and call blocking, easy mode and Do Not Disturb, as well as popular gestures (like Direct Call) and Smart Stay. An area for installing themes has also materialized (there are three in my review unit so far). Kids Mode (and many, many others) hide out in the Galaxy Apps app, but other erstwhile tools, like the S5's floating Toolbox of shortcuts, get the boot.

Here's another axed power-user feature: a fuller list of quick-access controls and settings that you see when pulling down the notifications shade with two fingers. Doing this brings down the same shade as swiping down with a single digit.

Preloaded apps

A few folders prepopulated by vendor apps buttresses the simplified look. There's a bucket of Google apps and services, and one for new partner Microsoft (this folder has Skype and OneDrive, for instance). Bonus: you can edit the folder color.

As for preloaded apps, a few Samsung programs remain, like Milk music and video and S Health, which are Samsung's answers to the iTunes Store and Apple Health, respectively. S Voice is another constant. To get more Samsung apps and partner apps, you'll need to open a shortcut and select them from the buckets marked Galaxy Essentials and Galaxy Gifts. One such Gift is Fleksy, a keyboard alternative that will come free with all S6 phones.

Now playing: Watch this: Hide preinstalled apps on the Galaxy S6 and S6 Edge

Some unwanted preinstalls are easier to disable than others (press Edit on the app tray), but you won't be able to jettison them completely. Default Android 5.0 might allow this; Samsung does not.

Extras: Fingernail sensitivity, parallax built-in

Samsung doesn't crow about it, but it looks like high screen sensitivity, an option on previous Galaxies, is built into the S6's display. Although the option has disappeared from the Settings menu, I was able to navigate the screen (but not the soft keys) using only my nail. Not so for my fuzzy chenille glove, though it should work with a more fitted leather variety.

Some of the preloaded S6 wallpaper gives you a small parallax effect when you rotate the screen from side to side; the background shifts slightly while icons remain in place. I noticed the effect on two wallpapers. It offers a tiny bit of extra dimension. You can obtain the same visuals with wallpapers on other phones.

Mobile payments up ahead

That improved fingerprint reader we talked about above isn't only for unlocking the phone. It also sets the S6 up for making mobile payments using Samsung Pay, which launches this summer in the US and South Korea. Although we're not sure which markets it'll work in next, we do know how it'll work -- here's our hands-on with Samsung Pay.

In the meantime, you can use Google Pay (with the S6's built-in NFC, or near-field communication, technology), or a variety of other payment apps. (Install Google Wallet, turn on NFC, and presto: Google Wallet appears in the NFC and Payment submenu under "Tap and Pay.")

Now playing: Watch this: Samsung Pay: Easy as a swipe and tap

Camera action

A 16-megapixel camera juts out slightly from the phones' back, sporting the same resolution we see on its big brother, 2014's Galaxy Note 4. The lens itself gets an upgrade over the Galaxy S5, to f/1.9, from the S5's f/2.2 rear camera.

The S6 and S6 Edge become the second wave of Samsung phones to include optical image stabilization (after the Note 4 and Note Edge), which should help smooth out shaky hand shots. A new auto-HDR (high dynamic range) feature means you won't have to stop to improve certain scenes, like landscapes. It'll automatically adjust white balance, too.

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On the front, Samsung installs a 5-megapixel shooter for wide-angle selfies, promising improved low-light photos. As with the Note 4, you can shoot a selfie by tapping the sensor on the back of the phone, and you can download a separate Samsung shooting mode that'll take a self-portrait from the phone's rear camera.

Lay of the land, extra modes

The native camera app looks clean and simple (and similar to that of the HTC One M9, probably because of the common Android 5.0 denominator).

On-screen controls on the left and right edges include effects and the timer, plus settings that dig deep into options like tracking auto-focus and voice control. Meanwhile, the Mode button on the right pulls up six alterna-modes for effects like panorama and slow-motion (hilarious on a 2-year-old!). Pro mode lets you more granularly adjust settings for macro and white balance, and Virtual Shot gives you a sort of weird GIF effect that I'm not sure anyone really needs.