Remember the days when text messages and Snake on your Nokia 3310 were two of the most exciting things a phone could manage? We do too. Fast forward 15 years and we have in-display fingerprint scanners,
punch-hole front cameras , bezel free displays and a whole new take on slider and flip phones.
Flip phones were once slim, compact and hinged devices. Now, flip phones have morphed into foldable phones and they are set to be unhinged, in both senses of the word.
With bendable screens, Android support, plenty of potential and huge price tags, here are the devices leading the crazy foldable smartphone trend, from the already announced to the upcoming and rumoured.
Huawei
6.6-inch front, 6.38-inch rear, unfolds into 8-inch OLED tablet
4500mAh battery with 55W fast-charging
Kirin 980 chipset and 5G modem
Leica triple camera
Huawei was the one to steal the show at Mobile World Congress 2019 , unveiling its take on a folding phone in the Mate X. Unlike the Samsung Fold (below), the X has its screen on the exterior fold - presented as a 6.6-inch main screen and elongated 6.38-inch screen on the rear. Unfolded, the two present as an 8-inch tablet form.
It's seamless, with no separation, no kinks or creases - and we think the Mate X is a much smarter implementation of the folding feature idea than Samsung's 'hidden tablet' in the Fold. However, the Huawei might struggle with scratches.
Elsewhere the Mate X offers top-end spec: its got a 4500mAh total battery capacity with fastest-in-class 55W charging (80 per cent in just 30 minutes), the company's top-end Kirin 980 processor and a 5G modem for the fastest possible connectivity. There's no final word on price or release date just yet, though, but Huawei being Huawei we'd expect it to be competitive against Samsung's offering.
Huawei Mate X in pictures
Samsung
7nm 64-bit octa-core processor, 12GB RAM
4.6-inch to 7.3-inch Infinity Flex display
512GB storage
4380mAh battery capacity
The Samsung Galaxy Fold is finally official, following years of rumours. The device was revealed alongside the Galaxy S10 range at Samsung Unpacked 2019 and it will go on sale at the end of April for the US and beginning of May for Europe, with a starting price of €2000.
The Galaxy F foldable smartphone has a 4.6-inch screen that folds out to an 7.3-inch tablet, but unlike the Royole FlexPai (below), it has a more consumer friendly design with a more considered hinge. It features a 7nm Exynos chip, coupled with 12GB of RAM and 512GB of storage. There is no microSD but the device does offer six camera and the software allows for three-app multi-tasking when open on the larger display.
Samsung Galaxy Fold: Everything you need to know
Royole
Qualcomm SD855, 6/8GB RAM
7.8-inch flexible screen, 308ppi
16MP/20MP cameras
134 x 190.3 x 7.6mm (unfolded), 320g
Royole beat everyone to the punch, announcing the first commercially-available smartphone with a flexible display. It's currently only available in China as a developer model but the FlexPai turns from a 7.8-inch tablet to a smartphone by folding in half.
It's got all the power of a typical flagship smartphone but it's a bulky bit of kit when folded and it doesn't fold flat, leaving a nice big air gap next to the non-existent hinge. It also starts at £1209/$1300. There's plenty of future potential though, especially given the screen technology is just millimetres thick.
Royole FlexPai in action
Xiaomi
President of Xiaomi, Lin Bin, tweeted a teaser video of a foldable phone so the trend is on the Chinese company's radar, though it wasn't ready for Mobile World Congress .
The device folds both sides, allowing for a smaller phone unit from the larger 4:3 tablet. The video shows the software adapting accordingly depending on the form factor, but Xiaomi's vice president told us the company is still studying what technologies should be offered.
Currently the device is just an engineering sample, though Bin said if it is liked by enough people, the company would consider developing a consumer version. He asked for name suggests. We are all about Foldy Mcfoldface.

TCL
TCL announced at Mobile World Congress 2019 that it will be entering the foldable smartphone market at some stage, though it doesn't yet have a specific device. Instead, the company showed off a hinge - called DragonHinge - that could feature on various foldable phone designs, as well as wearables.
There was also a prototype device at MWC, which opened and shut like a wallet. The screen was on the inside and while there was no external display, the company also showed a concept with a display on the cover, allowing users to check notifications and messages.
TCL is entering the foldable device game with versatile DragonHinge
LG
LG
Not ruled out foldable device
LG announced the V50 ThinQ at Mobile World Congress 2019 , but it isn't a foldable phone. Instead, the 6.4-inch device has a Dual Screen accessory that allows users to experience two screens together but they can be detached from each other. The Dual Screen comes in the form of a foldable case with a display and it connects to the V50 ThinQ via three pins.
The company hasn't completely ruled out making a foldable phone though. It told us in our pre-MWC briefing that a foldable phone doesn't make business sense just yet but that if things change in the future, it's something it might consider.
LG V50 ThinQ and Dual Screen accessory
OPPO
Oppo
Leaked on Weibo
Like Motorola and LG, Oppo has filed patents for a foldable smartphone. The company's product manager was reported to have said news regarding Oppo's foldable smartphone plans would potentially appear at MWC but not much else was said and nothing appeared at the show.
Instead, images of the device landed on Chinese micro-blogging site Weibo. The phone is clearly a prototype and has a OLED wraparound display on the outside rather than folding internally. Based on the images, one side of the screen has a thicker bezel for cameras and so on.
When the Oppo foldable phone will launch is not yet known but it certainly looks like the OnePlus parent company will launch one at some point.
Sony
6.2-inch, OLED, 4K
Dual rear camera (19MP + 12MP)
Qualcomm SD855
8GB RAM, 128/256/512GB storage
It's long been claimed Sony is also working on a foldable smartphone and several concept videos from Tech Configurations show just how amazing the device could be. With various names speculated, including Xperia Note Flex, it's claimed Sony's foldable device will take things to the next level and also offer a transparent display.
An in-display fingerprint reader, dual rear camera and Qualcomm's Snapdragon 855 chip are all listed specs in the concept leaks. The Sony Xperia folding smartphone is also said to have a polymer joint and a 6.2-inch OLED display with a 4K resolution when folded out.
LENOVO / MOTOROLA
Motorola
Internal and external display
Camera
Fingerprint sensor
Speculation suggests Motorola is quite literally morphing its 15-year old Razr flip phone into a foldable phone, switching the numerical keyboard for a full display that folds when you shut the phone.
It is claimed the Razr lookalike will not only offer a long internal display, but also a secondary screen on the rear, which will presumably show incoming notifications without the device needing to be open. A camera and fingerprint sensor also appear to be present, based on the leaked patent.
Apple

Apple has filed a couple of patents for foldable phones, suggesting the Cupertino company is also working on a device to meet this trend.
According to one patent , the Apple foldable smartphone may use "overlapping hinges" attached to "flexible displays".
Another patent suggests the device could roll rather than fold. Naturally, rumours are very contradictory but it has been said Apple will wait till 2020 to release a foldable smartphone so we might have a little longer to wait yet.