iPhone Duo review: Apple’s folding phone is a messy, expensive good time

The iPhone Duo is the riskiest Apple product in years. It’s a huge rethink of what an iPhone is and could be, and it contains the seeds of many fascinating ideas that might be great in the future.

But that future is yet to come. The iPhone Duo is also one of Apple’s messiest first-generation products in a long time, and right now it will delight gadget nerds and early adopters and likely frustrate everyone else.

It’s been a minute since the iPhone has looked or worked significantly differently. The last major change was the iPhone X, which dropped the home button almost a decade ago, and even that was a fairly subtle improvement. In fact, “subtle improvement” is really the entire story of the iPhone — it’s the foundation of Apple’s entire business, after all, and there’s a lot of risk in just up and changing it. You can see it in this year’s iPhone 18 Pro: It’s been refined in many ways, with better thermals and an interesting variable aperture lens, but it’s barely different than the iPhone 17 Pro.

But you can’t play it safe designing a foldable. You have to make some big decisions about screen sizes and what the inner and outer displays are for, and then make an even bigger set of decisions about how that big inner screen should work. All of those decisions are risky, and Apple’s riskiest decision was the Duo’s size and shape.

Apple’s single most important design decision for the Duo was to make it shaped like a passport.

The wide aspect ratio makes the inner screen friendlier for 16:9 YouTube videos, but it also marks a departure from the taller foldable design phone makers have embraced over the past five years. Prior to 2026, most folding phones opted for a tall-and-narrow shape to optimize for using vertical apps on the cover screen. But rumors started pointing to Apple going with its landscape-first form factor, and other foldable makers shifted gears — seemingly to get ahead of Apple. Now that the iPhone and a handful of competitors have adopted the wide format, they have to solve a new problem: designing a cover screen that will work well enough for vertically oriented apps.

The Duo’s 5.4-inch outer display is glossy, while the 7.6-inch inner display has a striking nano-texture matte coating. Apple’s very proud of this inner matte display, and for good reason — it looks and feels incredibly solid, a big step up from foldables with glossy, seemingly soft screens with glaringly obvious creases, like the Pixel Fold, and even the more subtle but still visible crease of the Galaxy Fold 8.

The matte display is indeed there to help hide the crease, which Apple keeps calling “perceptually flat” because it’s more fun to invent science-y marketing phrases than just saying “you mostly don’t see it.” But it’s true: You mostly can’t see the display crease, although you can definitely feel it. If you’re looking at a white image off-axis, you can see it, and there are moments in some lighting where it’s much more obvious. It definitely shows up more prominently on camera than it does to your eyes.

What you will see is the under-display camera, which reflects light in a more glossy way if you’re outdoors or in a bright area. Overall, though, the camera and display crease stopped being noticeable after a while. The crease also wasn’t any more noticeable after a week of constant flipping and folding, although we’ll see how it holds up over time.

That’ll be a real test, because Duo owners are going to be constantly flipping this thing open. Between Apple’s display aspect ratio and iOS design choices, the outer screen feels like much more of a status display than you’d expect — everything about the Duo gently nudges you to flip it open and use it in tablet mode. And not just tablet mode, but portrait tablet mode. That’s because iPhone apps are largely portrait, and the Duo is still very much an iPhone, even though its shape makes it fight all that history.

iPhones have gotten bigger over the years, but they’ve mostly stuck to the same basic rectangular aspect ratios: 2:3 from the first iPhone through the 4S, 16:9 from the iPhone 5 through the 8, and 19.5:9 from the iPhone X on to today’s iPhone 18 Pro. Basically, the iPhone has mostly gotten taller over time.

The Duo changes all of that — it’s the first iPhone that’s gotten shorter and wider. Both the inner and outer displays have a 1.4:1 aspect ratio, which was a very deliberate choice on Apple’s part, because they’re the same shape open and closed. This is clever in terms of display math and potentially great for app developers, but in practice it means that the outer display is really quite small, especially compared to modern Max-sized phones. If you’re texting someone in Messages with the keyboard onscreen, you’re lucky to be able to see two or three texts at once.

Apple has tried to reclaim some vertical space by scooting the UI elements of updated apps off to the right, but if you’re left-handed, that means using the phone closed with one hand can be challenging, even for someone with big hands. Having that strip of real estate along the right side occupied by navigation controls also means that using the Duo single-handed in your right forces you to reach farther when there’s something on the left side of the screen you need to tap. This means that you’re sometimes holding a fairly heavy phone, stretching for a small target that’s just out of reach, which isn’t particularly confidence-inspiring.

It’s also wild to have iPhone apps with controls in all kinds of different places; reaching for the back button in Apple’s Mail app and realizing it’s moved from the top left to the right is kind of disorienting. A lot of using the Duo is just figuring out how to use an iPhone again, which hasn’t happened in a long time.

If you’re using an app that isn’t updated for the Duo, you’ll see a black bar along the right side of the cover screen where those navigation controls would otherwise live. But even updated apps don’t feel particularly useful for anything other than a quick check-in on the cover screen. Apple says you’re getting 90 percent of the screen area of an iPhone 18 Pro, but that’s pretty small for today’s apps. It’s like having an iPhone 5 in a world of iPhone Pro Maxes.

This means that when you pull the Duo out of your pocket, you’ll almost always be looking at a tiny amount of information. And the second you want to really do anything, you’ll find yourself unfolding the phone to use the vastly larger and more useful inner display.

But you don’t get any additional height when you open the Duo up. Switching from a tiny portrait display to a bigger landscape view isn’t useful for most phone apps, which are all designed around big portrait displays. Most phone apps look silly this way, especially those still running as standard iPhone apps, which look normal but with lots of black padding on either side. It’s either cramped and tiny on the outer screen or a little silly and awkward when you open the Duo.

This means almost every time you open the phone you instinctively rotate it, and while it will work no matter how it’s rotated, it’s better to rotate it counterclockwise so the cameras are on top and the volume buttons are on the top left. Over our week of testing, this started feeling more natural, but it’s exactly the opposite of what you’d initially expect. It’s especially odd in Apple’s bumper case, which has a large notch to expose the Touch ID sensor and camera control, and it looks for all the world like it belongs at the bottom.

You might think this is a little thing, but it’s strange to find yourself slightly unsure of how to hold a smartphone. A nontrivial part of the Duo experience is just reorienting yourself to where the volume buttons are as you flip the thing around. When closed, they’re on top of the phone, but if you rotate the Duo clockwise, they end up on the bottom right, and it’s the top button that turns the volume down because they don’t change orientation with the display. There’s a buried setting in iOS that makes the volume buttons reorient themselves as you turn the Duo around; Apple needs to set it so it works right by default.

One other thing to get used to is simply unlocking the phone. Touch ID is integrated into the wake button on the side of the phone. There’s no Face ID at all, and it might take a minute to remember that when you stare at your phone for a beat and wonder why your notifications aren’t unfurling. Ask us how we know. But a week is long enough to get used to Touch ID life again, and it’s mostly painless once you remember you’re supposed to be using it.

Now, here’s the thing: This is all pretty fun! The iPhone has been the same for so long that being forced to come up with little moves and tricks and ways to think about holding the Duo is a gadget nerd thrill. Other foldables do this too — Samsung and Google and Huawei have been pushing the envelope of gadget-y smartphones for ages — but Apple’s played it so safe for so long that the Duo is legitimately surprising. But Apple hasn’t found some magical software solution to making a product with this much inherent complexity any less chaotic. It just happens to be the kind of first-generation chaos that will delight early adopters and lead most everyone else back to their regular old iPhones.

That first-generation wonkiness is most obvious in the software, especially in how the Duo supports third-party apps. Almost everyone who sees the Duo assumes that it simply opens up into being an iPad, but that’s not how it works at all. In classic Apple fashion, the company decided to throw everything out and start over.

That means getting rid of a lot of weird iPad baggage, but it also means that solved problems on the iPad are back on the Duo. It’s big stuff and little stuff: For whatever reason, the Duo doesn’t support pinching the keyboard to make it smaller and friendlier to use one-handed — a feature iPads have had for ages. It also means there are new ways to think about multitasking, and sometimes you’ll be unsure what will happen when you swipe around the screen because apps interact with iOS and each other in very different ways.

If you want to run two apps at once on the Duo, you swipe up and over to pin an app to one side, and then pin another app to the other side. If you tap on the little divider, you connect the apps into a set, and you can come right back to it in the app switcher. It’s neat, but it only works in landscape. If you want to have two apps open when you’re holding the Duo in portrait mode, you’re basically out of luck — unless what you want is to watch a video on the top while scrolling an app on the bottom. In that case, you need to make sure you have an app that supports background video, open that app, start the video, close that app to initiate the floating video window, open your other app, and then (and only then!) find a little button in the floating video window and hit that to pop everything into place.

This is legitimately cool once you figure it out. But you will note that this is a totally different approach to multitasking than any previous iPhone or iPad, and nothing about the Duo’s interface makes it obvious that it can work this way. It’s a lot of these little moments of figuring it out for yourself that really solidify the Duo as an early adopter special — especially since some features only work in some apps sometimes. That floating video feature? Yeah, it works with YouTube TV, but it doesn’t seem to work with regular YouTube.

This is initially surprising, because the YouTube app appears to be at least a little updated for the Duo. But it turns out that right now there are basically three ways apps work on the Duo.

First, there are regular iPhone apps that haven’t been updated at all. As with an iPad, you can zoom and rotate these apps to make things a little more useful, but they look pretty silly. This is the vast majority of apps right now, although we saw lots of apps get updated to the second category during the course of our review.

The second category is what you might call the messy middle: apps that have been updated for iOS 27. They get some automatic layout fixes so they’ll automatically expand to fill the inner screen in landscape orientation and don’t look quite as silly as standard iPhone apps. But you can tell they haven’t actually been designed for these displays, and those rough edges are super obvious. The telltale sign of these apps is the black bar on the right when you use them on the cover screen — proper Duo apps add controls to that space, but these in-between apps don’t.

Then there are fully updated Duo apps built for the Duo-specific iOS 27.1 — we got to test a few of these, and they can be pretty good. Instagram’s Edits app is a perfect example of why a folding phone is useful. It opens into a full video editor with a big timeline and nice preview window, and you can just get things done. And even in the span of the past week that we’ve been using the Duo, we’ve seen some apps, like Slack, go from the messy middle to fully updated. This makes a big difference in how useful they feel on the inner screen, but obviously doesn’t address the reality of the small outer-screen real estate.

Developers will need to have either a lot of energy to create neat stuff that takes advantage of the Duo’s form factor or a lot of encouragement from Apple. Maybe both. Either way, we have to hand it to the Deck-Man app, which reformats Apple Music into a little virtual Walkman. The page-turn animation in Books is terrific. And if you’ve ever dreamed of reading PDFs on a big screen in the back of an Uber, know that they look particularly great on the matte display.

But the reality is you’re going to see a lot of tiny iPhone apps and apps in the weird unoptimized middle zone for a while. It’s all just messy, in a lot of the same ways Android foldables are. That’s particularly surprising because the Android tablet app story has always been messy, but Apple had the whole ecosystem of iPad apps waiting at the ready. For whatever reason, the company just didn’t go that way, and that means it will take a while for the Duo’s app story to settle down.

Versus the Samsung Galaxy Z Fold 8

The Duo’s most obvious competitor is the Galaxy Z Fold 8, which Samsung managed to sneak out a few months ahead of the Duo. They’re both wide folds, but they’re not exactly the same. The Fold 8’s front screen is slightly taller and narrower, and the Duo is noticeably thicker and heavier. Those details add up to a big difference in how it feels to use the cover screen, especially one-handed. The Duo is pretty hard to use single-handed, but it feels doable with the Fold 8.

Apple also insists on preserving the more narrow vertical aspect ratio when you use an app on the cover screen by reserving that strip on the side for controls, whereas Samsung lets content occupy the entire width of the screen. On the larger inner display, Samsung offers a couple of options to make the keyboard friendlier to use. You can switch to a one-handed option that’s easier to reach or a floating keyboard you can move around and resize. And lots more Android apps readily take advantage of the full inner screen because foldables have been a thing on Android for quite a while now.

Apple is really emphasizing the ability to use the Duo in a variety of postures, including that kind of “I’m reading a book” situation where it’s partially closed. You can prop the phone up in tent mode and use it as a clock or digital photo frame. If you use it as an alarm, you’ll get a nice glow from the inner screen that’s supposed to help gently wake you up. You can watch videos on half of the inner screen in laptop mode, or on the outer screen in tent mode. Weirdly, Apple is actually more liberal in this than Samsung. The half-open position is called Flex mode on other Galaxy foldables, but the Z Fold 8 doesn’t let you use it, probably because the hinge isn’t stiff enough all the way through its range of motion.

Another important difference: The Duo is rated IP68 for full water and dust resistance, while the Z Fold 8 is IP48, so it isn’t fully dust-resistant. Neither phone should be used carelessly at the beach, but that higher dust rating offers a little more peace of mind.

Overall, these feel like pretty familiar moves for both of these companies. Apple wants you to use its phone its way. Samsung is less hung up on details like aspect ratios and where the keyboard can be. As always, Apple’s phone works best the deeper you are in the walled garden. The Duo feels a little more polished, but the Z Fold 8 has the better cover screen experience. Given how much of the experience of a foldable is reliant on the cover screen, that counts for a lot.

Performance and battery life

We each tested our own review units under pretty different circumstances over the past week, so it’s not surprising our battery life experiences differed. Nilay used the Duo just like he would during any other workday, using Slack, Google Docs, and Safari, and watching YouTube TV, Instagram, and TikTok. He needed to charge the Duo at least once to get through the day. This matched his usual experience with regular Pro iPhones, although the MagSafe battery packs he uses to get through the day are made for taller iPhones and don’t fit the Duo very well.

Allison was traveling more with the Duo, and spent more time watching video on Wi-Fi on her flights and scrolling social media. She had about 30 percent left after about 6.5 hours of screen-on time, which is decent. But as ever, iPhone battery life tends to vary dramatically for everyone, and change a lot over time. That’s even more so the case with a foldable — the more you use the inner screen, the worse of a time you’ll have with the battery.

Performance-wise, the Duo has an A20 Pro chip, and Apple says it has the same improved vapor chamber thermal management system as the iPhone 18 Pro. For most things it’s plenty fast, but the reality is that it’s also a thin phone driving two big displays, and it definitely gets warm, and sometimes hot. We saw this happen in two places: third-party apps, particularly video apps and Google’s apps, caused things to get hot. The first-generation nature of the Duo really came through here, and it’s something we would hope would improve as various apps get updated.

The phone also heats up when you use the camera for a long time — especially features that use the camera and both displays at once, like Duo Preview and Kid Cue. You can just feel the phone getting significantly hotter when this happens. Add in processor-intensive camera features like Smart Take, which automatically hits the shutter button, and the phone gets hot enough to start noticeably lagging after a while.

You’d hope Apple can improve battery life and thermal management over time — it has certainly done that with other iPhones in the past. But the Duo today gets hot, and doesn’t seem ready to last a full day of heavy use. Those are real compromises on a phone that starts at $2,000.

The Duo’s other big compromise is camera quality. It has a smaller main camera sensor than the one you’ll find in the 18 Pro and is instead on par with what you get from the iPhone Air. That’s fine for grabbing everyday shots, but it’s fundamentally a notch below flagship tier. The Duo relies on heavier sharpening to make up for its weaker hardware, so fine details look a little crunchier than they do on the 18 Pro. The Duo retains a bit less color detail in low light too, though Night Mode kind of evens out the playing field between them.

Some of the manual controls on the 18 Pro are absent here, too. There’s no shutter speed and no moving aperture, but you do get white balance and manual focus controls. The biggest concession is that there’s no telephoto camera here. You get that 2x crop zoom and up to just 10x digital zoom. There’s a 48-megapixel ultrawide that’s fine, but you just don’t have the flexibility you’ll find on basically every slab phone that costs half as much as the Duo.

The 12-megapixel Center Stage selfie camera on the front screen is a little worse than the 18-megapixel one on the 18 Pro — again, it looks like it’s compensating for its lower resolution by oversharpening details. There’s also an under-display FaceTime camera on the inner screen that’s okay in good light but really quite bad in dim light. (Apple won’t say the FaceTime camera’s resolution, but it’s just 4 megapixels.) Overall, it’s serviceable for a video call, but not much else.

But the good thing about a folding phone is that every camera on this thing is a selfie camera. You can open it up and preview your image on the front display while you use the much better main camera to take a photo of yourself. You’ll actually want to use the camera control button on purpose for a change, because it’s the only sensible way to press the shutter when you have the phone facing you like this — there’s no on-screen shutter and the volume controls are right next to the lens.

Apple’s Kid Cue takes a page out of Google’s book by using the front screen to play animations designed to get your kid looking at the camera. It works, but your subject will be looking off to the side since the Duo (wisely) uses the better main camera lens rather than the selfie camera for this. But if you’ve ever tried to get a young kid to look at a camera and make a normal face, you’ll probably agree that this is close enough.

Outside of that, the form factor lets you do a couple of fun things with the camera. You can set it up in laptop mode or standing up like a book to shoot a time-lapse. There’s a feature called Smart Take that will automatically snap photos when it senses that subjects in the frame are striking a pose that’s kinda fun. (It would be cool if you could switch the image preview to the other panel to use it halfway open like a waist-level viewfinder, but you can’t.)

The main camera records up to 4K/120 video and it will let you apply Cinematic mode to your clips after capture like the 18 Pro does. You also get the new texture controls in Photographic Styles if you want your foldable phone camera to act more like a film camera. Still, you’re definitely not getting the latest and greatest iPhone camera, which is weird on a $2,000 phone — though that’s certainly not unusual for a foldable.

On the other side of the aisle, Samsung basically split its Fold series into two models: the wide one with less-good cameras and the portrait-oriented one with a better main camera. You can’t have everything — unless you have access to foldables sold in China, in which case, yeah you can. The bottom line is that the Duo offers a totally acceptable camera for a new iPhone, but it’s far from the best iPhone camera you can get.

There’s a lot of other little stuff to say about the Duo — it’s full of new ideas and weird little details keep coming up the more you use it. The Duo has MagSafe, unlike the Z Fold 8, which is a big quality-of-life improvement. Allison found that a PopSocket made the Duo way easier to hold, while Nilay had a less-good time trying to use his existing MagSafe battery packs on the phone. He also has MagSafe mounts around his house and stuck the phone up all over the place, with entertaining results. Who hasn’t dreamed of having a tablet in the shower?

You can use the Duo like a tiny little laptop, which is adorable, and it connects to a portable keyboard for some purse computer action. You can also watch movies and TV shows with it slightly bent, so it stays open on a table in tent mode. (It takes a second for the phone to figure out that you want to do this, but it gets there.) If all of this sounds stressful, then the first-gen foldable life might not be for you. But if you’re itching to try some of this out for yourself, then you just might be the kind of early adopter who will have a good time with the Duo.

The hard rule at The Verge for 15 years now is that you have to review the product that’s in the box — not the idea of the product, or all of our hopes and dreams, or even the promise of software updates to come. (And boy, does the Duo have a lot of software and app updates to come.) There’s a lot of potential in the Duo, but right now it is a first-gen device in every possible way.

It is expensive, it’s full of compromises, and it can be incredibly frustrating to use. Switching from the Duo back to one of our standard slab phones to get something done often felt like a relief. Sometimes you just need your iPhone to do what you need it to do — that’s why Apple has been so risk-averse in changing it.

But all of the risk and weirdness of the Duo is also fun, in the way the best early adopter devices are fun. It’s incomplete as a product, but complete enough as an idea that you can see where things are going. It’s reminiscent of the very first MacBook Air, which took exactly no one by storm — it took a full redesign for Apple to get it right, and then it took over the entire industry.

We’ll see what happens with the Duo, but as it stands, it is very much an open question whether Apple made the right choices about the Duo’s screen sizes and aspect ratios. Most Duo owners will find that the cover display is simply too small to use all the time. Avoiding the entire iPad app ecosystem is another choice that might not age well; so is asking developers to jump on board with a device that’s clearly destined to eventually run into the iPad. Apple also made some very real compromises around the camera, and we’ll need to do a lot more testing to understand the Duo’s performance and thermal management story.

But the Duo is a more cohesive idea about foldables than most of its Android competition, precisely because Apple has a better app and developer story to lean on. Right now the problem for most Android foldables is that the inner screens aren’t that useful so there’s no super compelling reason to open them. The problem with the Duo is that the outer screen isn’t useful enough, so you want to open it all the time, and Apple’s ecosystem means that eventually the apps will be useful on the inner screen.

But the real answer is somewhere in the middle — for both screens to be interesting and useful. Someone’s going to get there, and we’ll see if Apple can be the first.