Hardware

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.

Flexing

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.

Self-healing

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.