Nearly a decade ago, the iPhone X changed how Apple designs its phones, and its influence is still visible today. Now, with John Ternus stepping in as CEO and the $1,999 iPhone Duo arriving as Apple’s first foldable phone, the company appears to be entering another major shift that could shape its next generation of hardware. In our iPhone Duo review, we found a device that is heavy, expensive and late compared to Android foldables. Still, it borrows the best ideas from its rivals and revives features other manufacturers seem to have abandoned. Many apps still need updates to take full advantage of the Duo’s design, but overall, Apple’s first foldable iPhone was worth the wait.
Design and displays
Going from one screen to two opens up a lot of possibilities for phone makers, but it also introduces plenty of risks. Make a foldable too slim and it may not survive daily use. With two displays in play, the transition from one panel to the other matters even more. Apple’s answer was a design built around strength and consistency, though the tradeoff is a phone that weighs noticeably more than its closest rivals.
The iPhone Duo’s cover display is a glossy 5.4-inch OLED at 1,878 x 2,670 resolution, with 120Hz ProMotion and peak brightness of up to 3,000 nits. Open it up and you get a larger 7.6-inch inner panel at 1,398 x 2,034, which shares the same 1:1.4 aspect ratio and the same high brightness. As a result, moving between the two screens feels seamless. You see the same home screen and the same layout on both, just with twice the space on the inside. Apple’s opening animation also adds a nice touch that ties the two displays together.
The one major difference is on the inside. Instead of a glossy finish, the iPhone Duo’s main display has a matte nanotexture coating that does a few things at once. It protects the flexible panel underneath, cuts down on reflections and helps hide the crease. To be clear, a small divot still runs down the middle of the inner screen, and it’s easy to spot if you look at the right angle. Viewed head on during normal use, though, the crease practically vanishes. One word of caution: the nanotexture layer can be peeled away if you pick at it too much. Apple will replace it for $49, but unlike some Android foldables, the Duo gives no warning during setup that only Apple-certified technicians should remove the film.
Even so, both of the iPhone Duo’s displays deliver excellent image quality. The cover screen is a great size for one-handed use, and the textured surface of the inner panel should make drawing or taking notes with the Apple Pencil feel natural, with Apple Pencil support arriving later this month. The strong matte finish also makes comics and anime look better than they typically do on glossy screens. The one small trade-off is that colors look slightly less vivid on the inner display in bright rooms, though that difference disappears at night.
The rest of the iPhone Duo is just as well built. A sturdy titanium chassis holds it together, and its hinge is one of the smoothest I’ve used on any foldable. Apple says the hinge is made up of more than 100 separate components, yet you’d never guess it from how effortless it feels in use. The Duo can stay open at a wide range of angles, and the force needed to unfold it changes the further you open it, which makes switching between screens feel more refined. Apple also managed to give the foldable an IP68 rating for dust and water resistance. In the US, the only other foldable line with that rating is the Pixel 11 Pro Fold.
One notable change on the iPhone Duo is the lack of Face ID, which is standard on modern iPhones. Instead, Apple built a Touch ID sensor into the side lock button. It may seem like an odd choice, but for a foldable designed to be used in many positions, placing infrared face scanners on both the inner and outer displays makes little sense. The fingerprint sensor is very accurate, though unlocking takes a little longer than you might expect. Apple says the approach also feels more consistent with other Touch ID devices, such as iPads and MacBooks. According to the company, it also lets the phone wake up and show notifications on the lock screen before you unlock the full device.
The main drawback of the iPhone Duo’s sturdy build is its weight. At 254 grams (8.96 ounces), it is more than 25 percent heavier than the Galaxy Z Fold 8, even though the Samsung foldable has the same number of cameras and larger displays. Adding a case makes it heavier still. The extra bulk is significant: in loose pants the Duo can feel like an anchor in your pocket, and during longer sessions you’ll probably want to hold it with two hands rather than one.
Performance and software
The iPhone Duo runs on the A20 Pro chip, the same processor found in the iPhone 18 Pro, so performance is never a concern. I won’t go on about benchmarks, but the foldable delivers strong frame rates in games, and running apps side by side feels effortless. You can technically even play two games at once, though at that point the bigger challenge is having enough fingers and focus to keep up.
Multitasking on the Duo is easy to set up and there are several ways to do it. Press and hold an app to open a menu with a split view option, or swipe up and hold, then drag apps to the left or right and the phone snaps them to either side of the screen. You can also pin two apps together using the small tab in the middle, so opening either one automatically launches both in split view. This works well for pairs like email and calendar, which I often want visible at the same time. Split view also works when you hold the iPhone Duo vertically, but in that orientation the apps stack top and bottom instead of sitting side by side.
To suit the Duo’s wider displays, Apple made some major changes to the standard iPhone interface in iOS 27. Whether the phone is open or closed, the row of home apps sits along the side of the screen (usually the right), while status icons like Wi-Fi and battery level, along with anything that would normally live in the Dynamic Island, move to the top right corner. It’s a sensible layout that lets full-size apps run without interface elements getting in the way.
The one big catch is that the iPhone Duo is Apple’s first foldable, so many third-party apps haven’t been optimized for it yet. Apple’s own software doesn’t have this problem, and it’s clear the company put real work into making the most of the Duo’s design. The App Store and Contacts, for example, now use a dual-pane layout that shows off the large inner display. There are subtler touches too: when the phone is bent in half, interface elements shift away from the center, where touching the display would otherwise feel awkward. The Duo also supports halfway-closed positions on a table, which is great for taking photos without a tripod or watching a video while you eat.
Unfortunately, a lot of other software still hasn’t been updated, and Telegram is one of the biggest offenders. Even on the iPhone Duo’s large inner display, the app opens in portrait orientation with wide stretches of empty space on both sides. Apple offers buttons that rotate the app and expand it into landscape for a better fit, but the result is still far from ideal. Games have the same problem: Sword of Convallaria runs in landscape by default, yet still shows significant letterboxing at the top and bottom of the screen.
Google has spent several years pushing adaptive layouts for Android apps, so Android foldable owners rarely run into these issues. At times it almost feels like Google and other developers are snubbing Apple, since apps like Gmail have custom interfaces on Android foldables but no equivalent on the Duo. That’s more likely a sign of how new the device is than anything intentional. Developers will probably update their apps over time, and some big names, including Netflix, Instagram and OpenTable, have already adapted to the Duo. Still, the gap between optimized and unoptimized apps is the biggest growing pain on Apple’s first foldable.
Cameras
The iPhone Duo’s main camera system uses dual 48-megapixel rear sensors, giving you 2x optical zoom and two focal lengths: a 26mm-equivalent primary lens and a 13mm ultra-wide. On the outside, a 12MP Center Stage camera sits in the top right corner of the cover display for FaceTime calls and selfies. All three cameras capture sharp, detailed photos. In side-by-side testing against the Galaxy Z Fold 8, the Duo easily matched Samsung’s image quality, and in some situations, such as low-light shots, Apple’s foldable produced better-exposed photos with more accurate colors.
The Duo also supports advanced features like 4K video recording at up to 120fps and the same adjustable Photographic Styles found on the standard iPhone lineup. A few Duo-specific extras stand out too. The cover display can show subjects a preview of the shot when you use the rear cameras, and Kid Cue helps draw out a genuine smile when you photograph children, though similar features already exist on Android foldables. Still, if you want the best camera hardware Apple offers, the iPhone 18 Pro remains the better choice, thanks to its variable aperture lens and longer zoom range.
One of the Duo’s best features is the under-display camera beneath the inner screen. Instead of a standard punch-hole, Apple changed the sub-pixel layout above the camera so light can pass through, which means you can still take photos without a black dot on the screen when the camera isn’t in use. Samsung introduced similar technology on the Galaxy Z Fold 3 but dropped it with the Z Fold 6. Apple has brought it back in a more refined form, and it adds to the immersive widescreen experience of the Duo’s main display.
Battery life and charging
Apple doesn’t publish official battery capacity specs, but leaks suggest the iPhone Duo has a cell of around 4,883 mAh. In a local video rundown test, the foldable lasted 28 hours and 48 minutes. That’s about half an hour longer than the Galaxy Z Fold 8 (28:14), though short of the Moto Razr Fold (31:00), which packs a larger 6,000 mAh battery. Real-world battery life often feels even better. Even during testing, which included running several benchmarks and extended multitasking, the Duo routinely had 40 percent or more left at the end of the day. Depending on how hard you push it, two days between charges is realistic for some users.
When it’s time to recharge, Apple says the Duo can reach 50 percent in 20 minutes with a 60-watt power adapter, or in about 30 minutes with a slower 35-watt charger. Apple doesn’t make its own 45-watt charger, but the company says that’s all you need to get the Duo’s maximum wired charging speed. If you prefer wireless charging, the trade-off in speed is small: the Duo supports Qi2 chargers and MagSafe accessories at up to 25 watts.
Wrap-up
Gadget fans often repeat a familiar warning: don’t buy first-generation devices. New form factors are exciting, but they also tend to be real-world experiments. The iPhone Duo is different because Apple let Samsung, Google and other rivals refine foldable phone design for several years before releasing its own. That gave the company time to learn from their successes and mistakes, and the iPhone Duo avoids most of the growing pains a new product category usually faces.
The result is a foldable iPhone with a refined design and a lot to like: a beautiful inner display, a tough titanium frame, great battery life, solid cameras and excellent performance. The Duo’s more vertically oriented interface will likely need some tweaking over time, but it fits well with Apple’s approach to mobile multitasking.
At a starting price of $2,000, the iPhone Duo is extremely expensive, and I wish it weren’t so heavy. Unfortunately, that’s the going rate for a premium foldable right now. Its biggest issue is that developers will need time to update their apps for the new design. When an app is properly optimized, the Duo feels more powerful and capable than any previous iPhone for multitasking. When it isn’t, things may look a bit awkward, but the experience is still very functional. Even as Apple’s first attempt at this kind of device, the Duo is a first-class foldable, and Ternus and company have delivered.
