The big new smartphone design trend for 2019 is the folding screen. As phone displays get ever larger, with some now bordering on tablet dimensions, the folding panel takes things back a step by allowing a phone to bend in the middle and therefore be both normal-sized phone and usable tablet.

The first we saw was from Royole in the FlexPai, which was rushed out for January's CES show, and the tech wasn't quite there yet. Then in February at MWC we were introduced to the Samsung Galaxy Fold (relaunched at September's IFA 2019) and Huawei Mate X, while TCL and Energizer showed us prototypes.

Fast-forward to September 2019 and we're expecting to see folding designs from LG and Motorola imminently, while Xiaomi has been working on a foldable phone for some time. Lenovo, Google and ZTE have also patented foldable devices. 

Those concerned about how they will protect these pricey, super-fancy new breed of phones, given that they won't fit in a traditional case, will be pleased to learn Corning is also working on foldable Gorilla Glass. All the foldable phones we've seen so far use plastic displays, which are not as tough as glass.

It's working on ultra-thin, bendable glass that’s 0.1mm thick and can bend to a 5mm radius, it told Wired, and is working at ways to combine its rollable Willow Glass with its tough Gorilla Glass. The tech isn't expected to be ready for a couple of years yet.

Samsung Galaxy Fold

After a four-month delay following issues with the display, Samsung has relaunched its Galaxy Fold which goes on sale in the UK from 18 September. The £1900 foldable phone will be available direct from Samsung or on contract exclusively through EE, and ships with wireless Galaxy Buds and a Aramid case.

The Galaxy Fold (reviewed here) was originally supposed to go on sale on 3 May. Various fixes and improvements include reinforcing the hinge and display, plus making the protective layer bigger to make it clear it's not supposed to be removed.

There's a 4.6in HD+ Super AMOLED screen on the outside of the device, which can be unfolded to reveal a larger 7.3in QXGA+ Dynamic AMOLED display that can display three apps at once. The exterior screen is not usable in this position, but App Continuity allows you to continue what you were doing on the smaller screen on the larger display.

Galaxy Fold has a total of six cameras, with three (16Mp + 12Mp + 12Mp) on the back, two inside (10Mp + 8Mp) and one (10Mp) on the front in its folded position.

The foldable Samsung phone features 12GB of RAM, 512GB of storage and a fast 7nm 64-bit octa-core processor. The battery is rated at 4,380mAh.

The phone uses a custom operating system called One UI, which is much more simplified than what we are used to seeing on Samsung devices, and optimised for one-handed use.

Samsung reportedly has two more foldable phones in the planning stages, with Bloomberg reporting that two very different designs see one phone much more like the Huawei Mate X below, with a large outer wraparound screen, and the other a vertically oriented clamshell with a small external display.

Read more about the Samsung Galaxy Fold here.

Huawei Mate X

Huawei may well have outdone Samsung with its Mate X, which was announced at MWC in February 2019. It folds the opposite way to the Galaxy Fold and has a more expansive near bezel-less display.

Unfolded it’s 8in but fold it outwards and that one display becomes a front display of 6.6in and a rear one of 6.38in. It’s pretty special at this stage, and the most ready-for-market foldable at the time of writing. 

The software is as yet unproven, and at €2,299 it is mightily expensive - but just look at it.

The Huawei Mate X will be when of the first 5G phones when it arrives, which is currently expected to be November. The company has reportedly given the Mate X a bit of a spruce up since we last saw it, with the phone expected to run a Kirin 990 processor and upgraded cameras when it does finally go on sale. It's also been spotted at TENAA with a new ToF sensor, and reportedly comes in two versions: 6GB RAM/128GB storage and 8GB RAM/256GB storage.

Huawei is also confirmed it is already working on its successor, which will arrive in 2020. It will swap out the metal rear for a glass panel, allowing for more screen area.

Check our first impressions of the Mate X here and learn more about availability.

LG Foldable Phone

LG is tipped to unveil a foldable phone at IFA on 6 September. The closest we've seen to a foldable phone from LG so far is the V50 ThinQ (pictured), which supports a second screen that sort of achieves the same thing.

Brian Kwon, who now runs the company's smartphone business, told journalists at a Seoul press conference in February that LG had "reviewed releasing the foldable smartphone when launching [its] 5G smartphone but decided not to produce it”.

According to the Korean Times, LG believes it is too soon for it to launch a foldable phone, and must instead focus on regaining its market position.

Earlier this year LetsGoDigital spotted patents pointing to an LG foldable phone with a transparent design, which sounds insane, but more recent patents seem more realistic. The site has since published renders based on more recent renders (pictured). 

There have also been a bunch of trademarks submitted for potential names for its upcoming phone, covering everything from LG Bendi to LG Flex, LG Foldi, LG Arc and LG Folds.

Motorola Razr V4

The WSJ reports that the iconic Motorola Razr flip phone will return as a foldable phone in 2019 - with a sky-high $1,500 price. It claims Motorola and Lenovo will partner with Verizon on producing 200,000 Razr V4 phones.

New information from Motorola's VP of Global Product, Dan Dery, points to an imminent release. Dery told Engadget the company had "no intention of coming later than everybody else in the market", which suggests we should see a launch before the summer.

Renders (shown above) of such a device point to it adopting a similar shape and format to the original Razr, but replacing the former physical keyboard with more screen.

Dery says he has been impressed by the design of Huawei's Mate X, but the outer-screen design could be easily scratched. Instead, Motorola is working on a "plastic OLED device with plastic film on top", but the screen will not be on the outside.

LetsGoDigital reports, citing an anonymous source, that the new Razr will indeed be a similar flip form factor to the original but have an internal flexible display rather than a numberpad. It will reportedly undercut the Huawei and Samsung foldable phones by using a mid-range processor and a smaller-capacity battery when it launches in the US in December 2019 or January 2020, with an EU launch to follow.

Xiaomi Foldable Phone

Xiaomi president Lin Bin earlier this year posted a video to Weibo that shows him using a Xiaomi folding device running MIUI software.

The phone in the video is revealed to have two folds, which allows a quarter of the display at either end to be folded back and wrapped around the device. The screen appears to remain active when folded.

Xiaomi reportedly told LetsGoDigital: "The double folding phone is the latest innovation by Xiaomi. One of the key components of the phone, the flexible folding screen, is co-developed by Xiaomi and its supply chain partner. Aside from the screen, its design, folding mechanism and MIUI adaptation are independently developed by us.

"Xiaomi is first in the world to present a double folding smartphone and has conquered the technical challenges posed in its three different form factors - double folded, single folded, and tablet form. Prior to finding the best solution, Xiaomi has conducted extensive research and experiments to develop a robust folding mechanism that will allow the flexible screen to withstand mechanical stress."

Korean outlet ETNews also reports that Xiaomi - and another Chinese brand, Oppo - are working with suppliers to obtain the necessary components for production of foldable devices.

Sources suggest the Xiaomi foldable phone might materialise in the second half of the year, perhaps with the name 'Xiaomi Mix Flex'. 

Google Foldable Phone

According to patents recently discovered by Patently Mobile Google is also looking to get into the foldable phone game.

The patents show a smartphone with a single inward fold, operating on a central hinge to form a clamshell-style device. 

Nothing else is known of Google's plans at this moment.

Apple Foldable iPhone

Amidst all this talk of foldable phones it's only natural that people would turn their attention to Apple: will there be a foldable iPhone?

In truth there is no hard evidence to suggest Apple is working on such a device, and history tells us it will probably hold off longer than other phone makers to see whether this is a trend that will stick.

But Apple does have patents alluding to a foldable iPhone, and in the past it has allegedly put in orders for foldable screens with LG.

Plus there's the fact that the many concept images of such a device already circulating point to genuine interest from consumers (that shown here was made by Dutch industrial designer Roy Gilsing for Foldable Phone News).

Cowen analyst Matthew Ramsay notes that Apple is in a difficult position due to its reliance on Intel modems. It is faced with a choice of launching 18 months after competitors with an inferior Intel modem without mmWave capabilities, sourcing a modem from its competitor Samsung, settling its disputes with Qualcomm, or purchasing Intel's modem business and producing the necessary parts itself. None of these options is ideal, reports Bloomberg.

Learn more about the possibility of a foldable iPhone.

Lenovo Foldable Phone

Lenovo's plans for a foldable device differ slightly from its competitors in that it's working on a vertically- rather than horizontally folding device - or, at least, it was.

Back in September 2018 the company filed patents with the WIPO for such a device that also has a secondary screen when folded, according to Let'sGoDigital. The site created the above render based on those drawings.

There's rather a large hinge on the rear, allowing you to choose where to fold the screen. 

ZTE Foldable Phone

ZTE's first attempt at a foldable phone is the Axom M (pictured above), but in essence it is two phone screens strapped together. Now the company is planning to properly address the foldable phone design, according to new patents unearthed by Mobiel Kopen.

With a design very similar to that of the Galaxy Fold, with a front display that is separate to the main tablet-size display, this truly foldable ZTE phone would have a flexible- rather than rigid screen.

The patent reveals an illustration but no description of how it might work:

ZTE foldable phone patent

From the drawing we can see a rear fingerprint sensor, mono speaker, USB-C charging port and dual-lens camera with LED flash.

TCL DragonHinge

At MWC 2019 TCL and sister company CSOT showed off a foldable phone prototype using its patented DragonHinge tech. We saw them behind glass and they are a compact take on foldables that are less flashy than Huawei or Samsung’s.

This is because TCL is, it says, dedicated to making these phones more affordable than rivals at around the $1,000 mark. Because of this, don’t expect to see one on sale until at least 2020. 

We’re also not sure if these phones will be TCL branded or be licensed to TCL’s brands like BlackBerry or Alcatel. Yes, you could have a foldable BlackBerry in 2020. We love tech.

Energizer Power Max 8100S

Energizer's upcoming foldable phone was hidden behind glass at MWC 2019. The hinge is not as, er, pretty as some of the other foldable phones we saw at the show, but the specs are pretty interesting.

For a start there is a huge 10,000mAh battery which, paired with that extra screen, makes this a beast of a device. Also beastly is the Snapdragon 855 processor and 48Mp camera, one of two lenses at the rear. There's also a 12Mp lens here, and 24Mp round at the front. The Power Max 8100S has 8GB of RAM and 256GB storage.

Only the outer display was visible at MWC, and it's a notchless 6in 18:9 panel. On the rear is a 8.1in 4:3 display with a Full-HD resolution.

No information was given on when the Energizer foldable phone would be released or how much it would cost.

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