LG G Flex review: a promising phone, but not one you should buy right now

It's not too often we get to review a product with a completely new form factor, but we relish the opportunity when we do. This time, we're taking a closer look at the LG G Flex, one of two curved smartphones that have come out of Korea over the last two months. The idea of a curved device is enough to pique anyone's interest, but there's one thing holding it back from mainstream acceptance: the price. Retailing for the US equivalent of $940, this unique handset isn't for the budget-conscious, and it isn't going to make your every dream come true either. To most potential buyers, the return on investment is pretty low; it's high-end, sure, but is it worth paying a $200 or $300 premium just for the shape? We believe you already know the answer to that, but keep on reading to find out if we agree with you.


Even though there are only two curved smartphones right now, LG predicts the market for curved displays will grow to as much as $2.5 billion by 2018. If that's the case, we're witnessing the beginning of something big. Perhaps it's appropriate, then, that LG's inaugural device is... well, big? At 160.5 x 81.6 x 8.7mm, the G Flex, which features a 6-inch display, could be considered large even compared to the LG G2 or the Samsung Galaxy Note 3. Still, it's actually a tad smaller than most other 6-inch handsets. The Lumia 1520 is just as thick as the Flex, but quite a bit taller and wider; even the 5.9-inch HTC One Max is taller and wider (and a great deal thicker). Both devices are also more than an ounce heavier than the 6.24-ounce Flex, making LG's handset feel comfortable by comparison. The sides are flat near the top, providing a place to rest your fingertips. Of course, they do curve inward toward the bottom.

That said, curves can bring a phone's ergonomics to another level. The Samsung Galaxy Round, which arcs from left to right, was much more comfortable than the Note 3 because its curves allow the phone to rest naturally in the hand. Since the G Flex arcs from top to bottom, however, it feels a little more awkward than it would if the phone were simply flat; my index finger frequently slips off the edge because the phone curves up and makes the sides harder to reach.

LG tells us that the G Flex has an "optimized curvature" of 700mm, a decision the company came to after testing more than 300 designs, each with varying curves. In particular, LG believes this is the most comfortable fit for most human faces. We agree that it's one of the most pleasant handsets you can put up to the side of your head, although this unfortunately means it's incredibly uncomfortable when you put it in your pants pocket -- especially if you're wearing tighter-fitting jeans.

There's certainly a coolness factor when playing with a curved phone, but what benefit does it really add to your overall user experience? The phone's flexibility, which we'll discuss shortly, protects the device from external forces; its banana shape means the mic is closer to your mouth than it would be otherwise. Also, the curves allow for more sound to reflect off of other surfaces, so speaker volume gets a boost. LG's also thrown in a flexible 3,500mAh battery -- we're told that the G Flex couldn't exist without being able to curve the battery -- which employs a stack-and-folding technique that's designed to offer more stability and better performance.

The glossy back cover comes with a brushed-metal look and is a little slippery, but as odd as it sounds, we don't mind it so much on the G Flex (more on that in a moment). It's also a huge dust magnet: It was nearly impossible to completely clean the phone, no matter how hard we tried. The G Flex uses the same rear buttons as we've seen on the G2 near the top, but this time the power button doubles as an LED notification light. Just above that, you'll find the 13-megapixel camera with flash on one side and infrared on the other. The buttons and camera rest on a small hump that rises just above the rest of the chassis.

Because all of the buttons are on the back of the phone, the sides look pretty clean. There's a micro-USB port and 3.5mm jack on the bottom, a micro-SIM tray on the left and a mic up top. On the front, you'll get a smaller notification light, along with a proximity sensor and earpiece. Covering the panel is a thin, curved sheet of Gorilla Glass.

The G Flex is currently available in Korea, but will soon be on sale in Hong Kong, Singapore and Europe. We're still awaiting word on whether it will get picked up by a US carrier, but for now, LG's keeping quiet about its plans. The company provided us with a Korean review unit, which comes with quad-band GSM/EDGE, CDMA (800/1900), tri-band HSPA+ 42 Mbps (850/1900/2100) and dual-band LTE-Advanced (850/1800). We weren't able to test the phone on LTE, but we had no problem connecting to AT&T's HSPA+ network. You'll also get dual-band WiFi with 802.11ac support, USB On-The-Go, DLNA and Bluetooth 4.0+LE.


Just as the name implies, the G Flex indeed offers a little flexibility, the likes of which we've never seen on a smartphone before. With the right amount of pressure, the banana-shaped device can actually be flattened, though it will revert to its original form afterward. LG told us it tested the feature by applying 88 pounds of pressure 100 times without permanently altering the phone's physical shape. Company reps wouldn't go as far as to give a maximum weight load, but we're guessing that putting much more pressure on the device is something they'd frown upon. Still, as we'll discuss soon, both the display and glass were built to withstand a decent amount of flattening.

In real-life use, we were satisfied with LG's claims. We did plenty of pushing and pulling on the device to test its physical limits, and none of our efforts resulted in cracking or any kind of damage to the chassis. Pushing down on the back immediately made us think of a large spring that offers only a little bit of give under enough pressure. Unless you've been doing a lot of finger push-ups lately, we don't think the flex feature is something you can take advantage of unless you go out of your way to do so; if you want to really flatten the device, you'll need to apply pressure with the palm of your hand, or pull on the edges of the phone like you're tearing a piece of stale bread.

LG reps explained to us that the phone isn't any more flexible than this because they felt the handset needed to retain a certain level of rigidity in order to still feel like a premium device. Sorry, folks, that means we can't have a Jell-o phone -- not yet, anyway. At the very least, the idea that this phone can handle external force inspires confidence in its durability, but what's even more important is what it means for future phones. Flexibility is going to be a critical component for curved devices going forward, especially as companies continue coming out with new form factors using bendable and foldable displays.


The G Flex is the first smartphone we've reviewed that comes with a self-healing finish, which is predominantly featured on the back. If this sounds familiar, it's because this kind of coating has already appeared on cars and is just now making its way onto consumer electronics. The idea is to help get rid of scratches and other small marks that can so easily show up on your phone. LG decided that the G Flex was a natural fit for it because its curves make the phone more susceptible to scratches.

Of course, the self-healing back isn't supposed to repair everything. The coating, which is elastic enough to allow the surface to bump back to its normal form, is still pretty thin and can only withstand a force of up to 500g. Unfortunately, this means you shouldn't be taking an X-ACTO knife or similar sharp object to the back of your phone as part of a bizarre party trick. As we mentioned earlier, it's only meant to take care of smaller marks created by keys and other objects that merely scrape your phone, rather than dig into it. The healing process is also faster at higher temperatures, so if you're in a colder climate, you'll need to apply body heat or a lot of friction to speed it up.

Naturally, we were excited to test out this feature; after all, how often do we get to damage a phone on purpose? After taking our keys and even a wire brush to our G Flex, we saw mixed results. Some of the scratches disappeared after just a few minutes; others were merely lessened (they weren't as noticeable) over time. Some of them didn't go away at all. We typically aren't fans of glossy backs, but this is one time we were glad to have it: Since the G Flex is glossy, the marks were hard to see unless we looked at the phone at just the right angle.

Flexible display

Before we discuss how the display looks, let's address another common question: Does the G Flex actually have a flexible display, or is it just curved? We're happy to report that it's not only flexible, but it's also much more so than we would've expected. Of course, this isn't so obvious when it's bonded to the G Flex's chassis, but we had the opportunity to handle one of the phone's displays when it wasn't attached to the rest of the body, and it's surprisingly similar to a plastic playing card. It's bendable in both directions and can even bend around my thumb -- LG said that it could tolerate up to a radius of 400mm. You can see a few pics of the display (as well as the battery and other internal components) in the gallery below.

Although resolution doesn't always tell the full story in the quality of a display, we were disappointed that the G Flex's Plastic OLED (POLED) RGB panel is only 720p. We consider this a mid-range spec these days, and it's even less acceptable when it's featured on a premium 6-inch device. LG didn't go into much detail on why it didn't use a 1080p display, but our theory is that the flexible tech is still new enough that the company couldn't mass-produce anything better than 720p. We'll give LG a few mercy points since flexible displays are in the early stages of production, but we definitely expect nothing less than 1080p on the next-generation model.

The lower resolution is clearly noticeable on the G Flex; text, graphics and videos just don't have the same kind of clarity that we've grown used to. However, there are quite a few positives that help make up for this shortcoming. The best part of the curved screen is its superb viewing angles, but in all fairness, we were highly impressed by the panel's viewing angles even when it was lying flat, so the curves simply enhance it. On top of that, the G Flex's screen is bright enough to read outdoors.

LG G Flex

Samsung Galaxy Round





160.5 x 81.6 x 8.7mm (6.32 x 3.21 x 0.34 in.)

151.1 x 79.6 x 7.9mm (5.95 x 3.13 x 0.31 in.)


177g (6.24 oz)

154g (5.43 oz)

Screen size

6.0 inches

5.7 inches

Screen resolution

1,280 x 720 pixels (245ppi)

1,920 x 1,080 pixels (386ppi)

Screen type

Plastic OLED

Super Flexible AMOLED




Internal storage



External storage


MicroSDXC (up to 64GB)

Rear camera

13MP, f/2.4, AF, LED flash, HDR (No OIS)


Front-facing cam



Video capture

1080p @30fps or 60fps

4K (3,840 x 2,160)






v4.0+LE, EDR


2.26GHz quad-core Snapdragon 800

2.3GHz quad-core Snapdragon 800





dual-band 802.11a/b/g/n/ac

dual-band 802.11a/b/g/n/ac

Operating system

Android 4.2.2, LG UI

Android 4.3, TouchWiz


If you've been following LG over the last few years, it may not surprise you to hear that the G Flex is not running the most up-to-date Android firmware (nor the preceding version). Instead, you'll need to survive on Android 4.2.2 Jelly Bean for now. We asked LG when we might expect to see KitKat, the latest version of Android, but so far the company has declined to comment. In other words, if you're going to buy the G Flex, make sure you love it for what it currently is, and not what you hope it will become.

Setting aside the version number for the time being, how is the software itself? It's much like what you'll enjoy on the LG G2 (the G2's knock-on feature is here), although there are a small handful of extra options that take advantage of the large screen and curved build. The most useful is dual-screen mode, which is LG's version of the Multi Window feature commonly seen on Samsung devices. Holding down the back button brings up a menu of 14 different native apps, which gives you the chance to pick which app goes on which screen. You'll be able to resize and flip screens as well as swap different apps in and out; we're also fond of the fact that if you have to exit dual-screen mode, the phone remembers where you were so you can choose to go back there whenever you want. It also has drag-and-drop capabilities, which allows you to do things like move pictures from your gallery directly into a message. Even more impressively, clicking on a link in a text or email lets you open that link in a second screen; this is a feature we've been anxious to have for a while, so we were happy to see that LG added it.

Dual-screen mode isn't the only feature that takes advantage of the extra screen real estate. LG also added the same one-handed features and gestures that we already enjoy on the G2, such as a one-handed keyboard and Slide Aside, which is a three-finger gesture that lets you save an app so you can return to it at any time without interruption. New on the G Flex, however, is a condensed set of virtual navigation keys on the bottom of the screen. By sliding the bar to the left or right, the already customizable set of soft keys moves to the side and the keys get closer together, making it easier for your thumb to reach them. It's a pretty smart addition that came in handy.

As usual, phones need a gimmicky feature or two that don't add any real value to the product other than general cuteness. Samsung's Galaxy Round has the roll effect, which allows you to get a quick glance at your notifications by rolling the phone to one side; the wallpaper on the G Flex's lockscreen scrolls up and down as you move the device in that particular direction.

Oh, and although we're not going to dwell too much on this since it's dependent upon our review unit's carrier (in this case, SK Telekom), we've never seen so much bloatware preloaded onto a device. Not counting the standard programs that come stock on most Android handsets, we counted more than 50 apps that either came from SK or were tied to one of LG's many "Q" services. Only a handful of them can be uninstalled.


The camera on the G Flex isn't any better than the manufacturer's flagship, the G2 -- if anything, it's slightly worse. Nearly everything is the same, such as the 13MP module with f/2.4 aperture and 3.97mm focal length, and it even uses a near-identical user interface. You'll still have the ability to change ISO, white balance, exposure and the other usual manual settings, and you can even switch from autofocus to manual, which can be a nice touch when it comes to experimenting with depth of field. You'll also be able to lock exposure and focus by holding down the shutter button, and you can use the rear buttons for shutter and zoom.

The same modes are still there, which includes HDR, VR Panorama, Dual Camera, Shot & Clear (Eraser), burst shot and intelligent auto. So what's missing from the G Flex camera? Optical image stabilization (OIS). Apparently it wasn't an oversight: LG told us that it had originally planned to add OIS, but the module would've been too tall to fit in the phone. This doesn't seem to have a huge impact on the quality of images taken in daylight, but it certainly has an adverse effect on low-light performance, which already wasn't as good as this year's Lumias and the HTC One. You can't capture as much light, which makes resulting images noisier and blurrier. Aside from this, our experience taking photos in broad daylight was just as good as the G2, which is to say it was better than average.

Although OIS is missing, LG at least threw in a brand new feature that you won't find on the G2 -- Face Tracking. Let's say you want to take a selfie or a group shot (with you in it), but you feel the 2.1 megapixels on the front-facing camera just simply isn't good enough to handle your glorious face. Easy: change the camera focus to "Face Tracking," turn the phone around and the power button lights up yellow when it's focusing, and turns to green when it detects your face. Then, all you have to do is press the shutter key on the back and presto -- 13MP selfie! Your self portrait has never looked better.

Performance and battery life

Qualcomm's Snapdragon 800 SoC has only been on the market for a few months, but it's already become the go-to chipset for flagship smartphones, and the G Flex is no exception. Indeed, this phone gets the superstar treatment: a 2.26GHz quad-core version accompanied by an Adreno 330 GPU and 2GB of RAM. It's no slouch when it comes to performance, but then again, neither was the G2, which featured the same setup. Thus, it should come as no surprise that LG has repeated its success story with the G Flex. In case you like benchmarks, here are a few to chew on.

LG G Flex


Nexus 5

Samsung Galaxy Note 3

Quadrant 2.0





Vellamo 2.0





3DMark IS Ultimate





SunSpider 1.0 (ms)





GFXBench 2.7 Offscreen (fps)










SunSpider: lower scores are better

Even more than numbers, what matters is the real-world performance. Fortunately, this is an area in which the G Flex passes with flying colors. It handles multitasking and dual-screen activities without hiccups, and we only saw the occasional skipped frame when playing games. Overall, we have no reason to complain about the performance, which -- let's face it -- is the most important aspect of actually owning it.

Speaking of which, a phone isn't worth much if you aren't able to use it for very long, so we're pleased to confirm that the 3,500mAh battery is exactly as it should be: long-lasting. In our video rundown test, the device hung through for 14 hours before dying, and at the end of an 18-hour day of higher-than-normal usage, our unit still had around 40 percent remaining. At this rate, we'd easily manage nearly two days with moderate use before needing a recharge.

Finally, the GPS was good most of the time, although we noticed that it occasionally stopped keeping track of our location, which grew frustrating at times when we needed navigation the most. We couldn't test LTE on this Korean version, but we managed to get HSPA+ speeds between 6 Mbps and 10 Mbps down and 1-3 Mbps up on AT&T. Sound quality, call quality and speaker volume were more than sufficient to do the job soundly.

The competition

Strictly speaking, the only competition the G Flex faces in terms of curvature is the Samsung Galaxy Round, which retails for around $1,000. Each has a completely different take on curved displays, and both have their own particular charms. Our spec sheet earlier in the review highlights the differences between the two devices in terms of components, which is a battle that the Round wins; Samsung's device is also more comfortable, but the G Flex offers a self-healing back, flexibility and better battery life.


More Info

The LG G Flex is a good phone, but there is no way in h-e-double-hockey sticks that we'd recommend that you go out and purchase a handset that costs more than $900 unless it also gives massages and does the dishes. (We're still holding out hope that this tech is in the works.) Of course, this is a nascent product category, and LG likely isn't expecting the phone to be a best-selling device; since all of the research and development for flexible screens isn't going to pay for itself, we're not surprised that LG is pricing this type of phone at a premium for now. In some respects, the G Flex is a cross between a status symbol and a proof of concept. We believe that the G Flex primarily exists for the sake of getting feedback from early adopters, so LG can continue to make its future curved devices even better. The cost will eventually go down over time as these phones get more popular, and once that happens, the curved form factor will become a much more reasonable buy. In the meantime, we'll sit back and admire LG's new creation -- and wait.

Edgar Alvarez contributed to this review.