Apple arrived late on the foldable smartphone market, but did not try to make up for lost time by simply re-proposing a formula already seen. iPhone Duo starts from the same idea as the foldable book of the main Android competitors, but interprets it with different proportions: when closed it is a small, wide iPhone similar to a passport; opening it becomes a device that is closer to an iPad mini than a traditional phone. It's the most profound change in the shape of the iPhone since the first model arrived, but not necessarily a revolution for the entire category. Most of its features already exist, in different forms, in the best Android foldables. The novelty lies rather in the way in which Apple has connected the hinge, display, cameras, processor and operating system together. The result is a first generation product that is more mature than expected in terms of hardware, but conditioned by some compromises in software and ergonomics.
iPhone Duo is available in Starry White and Night Sky. The frame is made of grade 5 titanium, with a polished finish that alternates with the micro-sandblasted treatment of the hinge cover. The latter is 3D printed and is the largest component of its type ever mounted on an iPhone, according to Apple. The dimensions illustrate the dual nature of the product well. When closed it measures 117.8 millimeters in height, 84.1 in width and 11.3 in thickness. When open the thickness drops to 5.2 millimetres. The weight is instead 254 grams, five more than the iPhone 18 Pro Max. It is therefore not a featherweight and, once closed, not even particularly thin. But in the pocket the weight and thickness seem to almost disappear: the phone is very comfortable in our opinion both to carry and to hold. iPhone Duo is a technological object built with precision and with a perceived premium quality, consistent with the price range.
The external Super Retina XDR display measures 5.4 inches, while the internal one measures 7.6 inches. Both are OLED, always-on and equipped with ProMotion technology up to 120 Hz, with declared peak brightness of 3,000 nits outdoors. Apple used the same 1.4:1 aspect ratio across the two panels, allowing content to resize without suddenly changing shape when you open or close the phone. The external screen offers 90% of the surface area of the iPhone 18 Pro but the short and wide shape significantly changes the display of applications. It is adequate for notifications, short messages, music, maps and photography, while activities that require a lot of vertical development invite you to open the device, even though you can do practically everything from the external screen. The internal display, however, is the main reason for wanting the iPhone Duo. The nanotexture coating diffuses light, limits reflections and makes the central crease almost invisible. The effect is different from that of the glossy panels traditionally used on foldables: the surface appears more opaque, retains fewer obvious fingerprints and is particularly pleasant to read. On the other hand, it requires more attention in cleaning and can slightly reduce the perceived brightness of the colors. In our tests, watching a film, reading a document, editing photos on the internal screen was a real pleasure for the eyes.
We were writing about the crease: it is not invisible, obviously, but it can be identified against the light and can be barely perceived by sliding a finger across the center of the display. During normal use the matte treatment manages to hide it really well, so much so that it rarely catches the eye. The hinge is made up of over one hundred elements and uses a variable torque profile, so the resistance gradually changes during opening: it can keep the phone still at different angles, making tent, small notebook and frame modes possible. The mechanical sensation is precise, but opening with one hand is not natural: the shape and strength of the magnets invite you to use both. And unfortunately, especially the first few times, we tend to accidentally touch the power button or the camera button. The phone is protected by Ceramic Shield 2 on the front, Ceramic Shield on the back and has IP68 certification against water and dust, a non-trivial feature for a foldable phone. However, the internal panel remains more delicate than normal glass: it contains a nanotexture polymer, layers of thin glass, flexible adhesives and a titanium plate designed to support them. As Kaiann Drance, Vice President of iPhone Marketing at Apple, explained to Sky TG24, "the creation of the iPhone Duo brings with it many challenges and a lot of satisfaction. We wanted the visual experience to be perfect - she says - and for the display to reduce reflections and at the same time be resistant. We wanted the phone to resist scratches and dents over time, and for the hinge to allow it to remain perfectly flat or closed at any angle. And complex engineering was required to achieve all this".
The fundamental question is not how spectacular the iPhone Duo is when opened, but how often you really feel the need to open it. Sometimes - and it often happened to us during the tests of other foldable phones - especially when we were in a hurry or found ourselves in situations that were not "comfortable" (on the street or on a crowded subway, so to speak), we ourselves avoided opening the screen, making do with the external one. And this is precisely what happened to us with the Duo too: we reserved the larger internal screen more often for reading, creating documents, gaming, choosing and editing photos, relegating quick replies on Whatsapp or reading and consulting emails to the external one. But here there is also the advantage, probably, of such a product: having two phones in one, and a format that becomes convincing and really useful when there is time and space to open it.
At the center of the iPhone Duo is A20 Pro, the same processor as the iPhone 18 Pro family. It is made - as Apple explains - with a 2 nanometer production process and integrates a 6-core CPU, a 7-core GPU and two 16-core Neural Engines. The RAM memory is not reported in the official documentation, the diagnostic findings circulated indicate 12 GB, but - we repeat - it is not a specification communicated directly by Apple. The most interesting element, experts underline, is not only the power of the chip, but the way in which it has been integrated. Instead of placing the memory on top of the SoC, the components are arranged side by side, according to an arrangement inspired by Apple's M series processors. The path of heat to the vapor chamber is thus more direct. A flexible layer of graphite also distributes thermal energy between the two halves of the phone. A20 Pro also integrates a specific engine for displays, which allows it to simultaneously manage two OLEDs at 120 Hz, the transition between the external and internal panel and compensate for the arrangement of pixels around the camera hidden under the screen. In daily use no uncertainties emerge: animations, games, photographic processing and multitasking are fluid. However, under prolonged loads the heat can become noticeable on the surface, and on several occasions it happened to us that the phone became hot. The memory sizes are 256 and 512 gigabytes, 1 and 2 terabytes. The initial cut is adequate for a product of this range, especially if you combine it with storage space on a cloud or on a NAS; the higher cuts are aimed above all at those who record a lot of videos or take a lot of photos.
The battery is divided into two cells, one for each half, but works as if it were a single unit. The autonomy varies mainly based on the time spent on the internal display and with mixed use we noticed that the phone behaves in a truly excellent manner, so much so that on some occasions it exceeded the battery life of the iPhone 18 Pro, even with intense days ending with 20-30 percent. The battery is compatible with MagSafe and the Qi2 standard.
The thin shape forced Apple to make a choice criticized by some: maintaining two high-quality rear cameras, while giving up a dedicated telephoto lens. The main 48-megapixel Fusion shoots at 24 megapixels by default, can produce 48-megapixel files, and allows you to select equivalent focal lengths of 26, 28, and 35 millimeters. The 2x zoom is obtained from the central part of the sensor and offers convincing optical quality, but it does not replace the reach of a real telephoto lens (and this is noticeable in the shots). The second camera is a 48 megapixel Fusion ultra-wide angle camera, the same used on the iPhone 18 Pro, with support for macro photography. On the external screen there is a 12 megapixel Center Stage front camera, while a second camera for FaceTime is hidden under the internal panel: the latter favors the visual continuity of the display over quality. Light must pass through the pixel layer before reaching the sensor, with an inevitable loss of detail and contrast. It's fine for an occasional video call, but it's not the camera of choice for selfies or important shots. As we have already noticed, the absence of a telephoto lens weighs on a phone costing over 2,300 euros, even though the photo performance is in many cases truly excellent.
"In iPhone Duo - explains Apple vice president Kaiann Drance - we have integrated an advanced camera system. There is no telephoto lens with 8x zoom of the iPhone 18 Pro, but thanks to a unique design features such as double preview, intelligent shooting and the possibility of simultaneous FaceTime are possible, allowing two people to join and see each other on both sides of the screen. We believe that the combination of all these elements represents the right balance for iPhone Duo, and of course those who need the more advanced camera system with telephoto lens can choose the 18 Pro, which remains a fantastic option within our range.”
The real contribution of the folding format is the possibility of taking photos in a different and innovative way. With Duo Preview, the person being photographed sees the frame on the external display and can independently correct expression and position, and for selfies the two 48 megapixel rear cameras can be used directly, with the external screen as a viewfinder. Smart Take leverages AI models. performed on the A20 Pro to follow the scene and automatically shoot when people are ready: it is designed for group photos in which whoever sets up the phone then wants to enter the frame without relying on a countdown. Furthermore, there is an Animation for children which shows animated characters on the external panel to attract the attention of the little ones. Additionally, the Duo can also be folded and stood without a tripod for time-lapse, video calls and long shots. Furthermore, with Duo FaceTime, a second person in the room can appear on the external display and participate in the call without having to huddle in front of the main panel. These are apparently superfluous functions, but in daily use they are really very useful.
The main camera produces detailed images, with a wide dynamic range and generally reliable balance. The processing maintains the “iPhone character”: controlled colors, excellent exposure and results ready to be shared without many changes. The ultra-wide-angle lens guarantees good color consistency compared to the main one and the high resolution also helps in macro photography. The 2x gained from the sensor is useful for portraits and tighter shots, but loses ground when the light decreases or you try to zoom in further. The photos taken at night are good: natural and not at all artificial. In addition to the absence of the telephoto lens (which as iPhone Pro users we have often noticed) the ProRes and Log formats are missing, but - as vice president Kaiann Drance explained to us, those who need a phone for professional photography can certainly opt for the 18 Pro and 18 Pro Max. The video performance is also good (the main camera reaches 4K Dolby Vision 120 fps) even if, compared to the Pro models, it seemed to us that the moving images were less stable. However, we could conclude this part dedicated to photography by writing that the iPhone Duo is an excellent cameraphone for general use.
Much can also be said about the iOS 27 operating system. Apple has moved the Dock, controls and navigation to the right side to free up vertical space, redesigned the status bar and placed the Dynamic Island in the upper right corner on both panels. When the phone is opened, the contents migrate to the internal display with a continuous animation. By rotating it or partially folding it, controls and windows move to avoid the hinge area. The keyboard changes configuration depending on the orientation and can split in two in landscape mode. We really liked Split View's multitasking: just drag an open application from the bottom to the middle of the screen and then move it to one side, and then open another app to place it on the other side and work with two applications at the same time. We found the system to be very intuitive and even easier to use than some Android solutions. Also very useful is the ability to drag photos, portions of text, files or links from one application to another (for example from the photo application to the email). It is also useful to be able to open two windows of the same application side by side, for example two web pages, or move a video to the top of the screen and work in the lower part. Note that the screen can "only" be split in two, both horizontally and vertically, but windows cannot be moved freely within the screen. As on the iPhone 18 Pro, European users cannot currently use the advanced artificial intelligence and Siri AI features on the iPhone Duo.
It is in the applications that you decide whether the internal screen is really useful or just "spectacular". Apple apps have been convincingly adapted. Mail, Messages, Notes and Reminders
