At Macworld we spend a lot of time wondering about the next generation of Apple devices. (If you share our curiosity, take a look at our iPhone 2018, iPad mini 5 and Apple Car rumour articles, and our What will Apple do in 2018? story.) But sometimes it pays to take a step back and think about the longer term, and the bigger picture. Where is technology going? What does the future hold? And what will Apple's smartphones look like in 2019, in 2020, even in 2030 and beyond?

In this article we discuss some of the paths smartphone technology could take in the coming years, starting with the iPhone that appears in 2019 (which might conceivably be called the iPhone XIs, although the naming convention Apple will be using by then is anyone's guess). If you want to know what kind of iPhone you'll be brandishing in the future, read on.

Most recently, sources have predicted that Apple will switch entirely to OLED screens in 2019, likely raising prices (and causing stress and stock value dips for LCD companies). And it looks like curved iPhones are in development and could be with us in within two to three years.

For advice related to the current range, see our iPhone buying guide and our roundup of the best iPhone deals.

iPhone 9 and beyond

Design changes

iPhones are that lethal combination of expensive and fragile that results in so much consumer heartache. The result is that each iPhone owner has to make their own deal with the devil: either wrapping it in a robust case, thereby masking the handsome design that they paid all that money for in the first place, or risk pavement damage every time they take the thing out of a pocket.

This may not be the case in the future, given the wide range of futuristic durable supermaterials that could be used on the iPhones of 2020. In this section we look at the design developments that could make the iPhone 9 and later tougher than you could possibly imagine... as well as other fun changes to the exterior design.

Below we look at some of the new design changes coming to iPhone design.

The notch

The 'notch' that takes a bite out of the iPhone X's display has provoked mixed emotions.

Many people dislike the way it reduces the amount of screen real estate developers have to work with, and find it distracting; others appreciate that Apple has used every available millimetre of screen - even going beyond the camera and facial recognition sensors on either side - and some even argue that it is an iconic and recognisable piece of design comparable to the Home button on the original iPhone.

Both parties will be interested to hear that rumours suggest the notch will get smaller in 2019 or maybe disappear altogether.

Back in January 2018 South Korea's ET News reported that Apple is "looking into combination of a face recognition module with a camera module", a move which would allow the company to shrink the notch - if it wants to. Then in March 2018 the same site claimed that Apple has found a way to get rid of the notch so that it can make a truly all-screen iPhone without having an area reserved for the cameras and sensors that are currently located behind the notch.

That site claims that a 'representative' told it that Apple intends to remove the notch from the 2019 iPhone and is already in talks with the relevant companies.

Removing the notch ay be made possible by a patent that Apple has just been awarded. This patent relates to displays with tiny, microscopic, openings in between pixels where sensors can be located. These openings would be too small to actually see, and the sensors would be embedded in the display itself, according to Digital Trends in March 2018.

Ceramic iPhone

A future iPhone could have a ceramic rather than metal case. An patent suggests that Apple is working on ceramic iPhone housings. The patent describes a way to manufacture ceramic iPhone bodies that are multiple colours - so perhaps it could be the future of the iPhone SE range.

It looks like Apple is considering placing coloured bars at the top and bottom of the back of the device, according to Digital Trends in March 2018.

Retractable screen

Apple has a patent that describes a portable device with a flexible OLED screen that upon releasing a latch retracts into two hollow casings and unfurls again when required, locking into place with support slats (a series of bistable metal members that become rigid when forced into a flat state).

The retractable screen recoils into barrel-shaped housings made out of aluminium or another suitable material. The speakers and microphone could be mounted in these housings as would the camera - or indeed cameras, with two cameras mounted far enough apart to be used to capture stereoscopic images. When closed the two barrels would be held together by magnets. There's more information about the patent over on Apple Insider.

We doubt that we will be seeing any iPhones following this design any time soon - one reason we think that this wouldn't suit the iPhone is that it looks like it would need to be used on a flat surface, holding it when uncoiled would be difficult. But we can see a retractable iPad being something that the future could hold.

Curved screen

Bloomberg's Mark Gurman reports that Apple is developing phones with curved screens - interestingly, he specifies that these are curved inwards from top to bottom, which would set them apart from the large number of horizontally curved devices currently on the market.

Citing a source "familiar with the situation", Gurman says the curved phones could be "as little as two to three years away". The development is possible now because of the OLED screen tech used in the iPhone X, which is easier to produce in shaped forms than LCD.

Nikkei has previously predicted the launch of a flagship iPhone with a curved OLED screen that curves down over the sides, quoting a source who is "familiar with Apple's plans". This is something we've already seen on rival devices, such as Samsung's S7 Edge and Note 7; it enables more screen space to be squeezed on to a device without making it any bigger, and you can also have notifications designed to be seen or activated on the edge of the screen.

Apple's Patent 9,146,590 refers to an "electronic device with wraparound display", and describes a curved screen that allows for more screen elements to be displayed without making the device significantly bigger. (Remember that the illustrations rarely represent what the designer has in mind. In theory the display could wrap entirely around the device, or at least extend over one edge like the Galaxy Edge.)

iPhone 9 rumours & patents: Wraparound screen

While the patent talks about a "flexible display assembly", it's important to note that this isn't a patent for a bendable screen: the flexible portion of the display is attached to the interior surface of the curved transparent housing, which "provides a rigid support structure that prevents deformation".

In August 2016, it was reported by Patently Apple that Apple filed patents for a curved glass iPhone with virtual buttons on the sides.

iPhone 9 rumours & patents

...or a bendable (or foldable) iPhone

In January 2015 Apple was awarded a patent that suggests that the company is investigating the idea of a flexible iPhone (and we're not talking about the Bendgate kind).

The patent suggests that, by making the iPhone flexible, Apple could unlock a new range of controls: the user could open an app by bending the device in a particular way, for example, or use the flexibility to control a game. It's an intriguing if seemingly far-fetched concept.

Additionally, a flexible iPhone ought to be more resistant to impacts and therefore more durable. But we'll discuss a key element in the idea of a flexible iPhone - a screen that can bend without breaking - in the screen tech section.

iPhone 9 release date rumours: Folding iPhone patent

An illustration from Apple's new patent. As one of Patently Apple's commenters points out, it looks a bit like an "iPhone DS"

As an update, in November 2016 Apple was granted another patent for a bendable smartphone, sparking further speculation that an upcoming iPhone could be designed with a folding chassis.

Patent 9,485,862, spotted by Patently Apple, refers somewhat obliquely to 'Electronic devices with carbon nanotube printed circuits': the carbon nanotubes are the means by which the devices can be folded. It was filed back in August 2014 but was finally granted on 1 November 2016.

"Carbon nanotubes may be patterned to form carbon nanotube signal paths on the substrates," reads part of the patent's summary. "The signal paths may resist cracking when bent. A bent portion of a carbon nanotube signal path may be formed in a portion of a flexible substrate that traverses a hinge or other flexible portion of an electronic device."

A further patent, spotted in late January 2017 by Patently Apple, describes "a flexible display that is movable between a folded position and an unfolded position", and a "fabric housing [that] forms a flexible hinge that allows the flexible display to be folded." And in October 2017, the Korean-language site The Bell cited industry sources in support of its claim that Apple has actually begun work in partnership with LG on a foldable OLED iPhone, with a goal of mass production by the first half of 2020.

Next: Battery and charging developments