Apple (video, MacRumors, Hacker News, Slashdot):

Apple today introduced iPhone Duo, the first foldable iPhone. Opened, it is the thinnest iPhone ever, with a 7.6-inch inner display that provides a large canvas for viewing content, gaming, and multitasking, and a special nano-texture finish that minimizes glare for an unparalleled viewing experience. Closed, the 5.4-inch outer display delivers 90 percent of the screen area of iPhone 18 Pro in a compact, pocketable design. Both displays share the same aspect ratio, so content scales proportionally, ensuring visual continuity. iPhone Duo is built to last with an innovative hardware design and a precision hinge that offers a smooth, satisfying feel with every use.

[…]

The 48MP Fusion Ultra Wide camera — the same as on iPhone 18 Pro models — captures wider fields of view and enables macro photography, while the Center Stage front camera can automatically take photos and videos in any orientation, so users don’t have to rotate iPhone for landscape selfies. Upgraded Photographic Styles with new texture and grain controls let users further dial in their desired appearance and have more creative control over their photos. […] The foldable design with dual displays unlocks camera experiences that are not possible on any other iPhone.

[…]

Lock Screen controls, the Dock on the Home Screen, and app navigation and controls now appear on the side to maximize vertical space for content. When iPhone Duo is open, the display shows two Home Screen pages with Today View — a vertically scrolling list of customizable widgets — on the left. The status bar includes a circular, flexible system that nestles into the corner of the screen, showing relevant information like Wi-Fi, cellular strength, battery, and more.

[…]

The expansive display supercharges productivity, letting users do more at once with new multitasking capabilities. Split View allows users to open two apps side by side on iPhone for the first time.

[…]

iPhone Duo is available in star white and night sky, and starts at $1,999, or $83.29 per month for 24 months, in 256GB, 512GB, 1TB, and 2TB storage capacities.

I love the idea of the larger screen and how it can be balanced half-folded like a laptop, upside-down, or on the short side. The camera is better than I expected. The price is high enough to make me lose interest but perhaps not unreasonable if it can actually replace your iPad. My main concern is that the wide passport-style shape doesn’t look very comfortable to hold or keep in your pocket. It’s great that it can unfold, but the compact form factor is how most people will probably hold it most of the time. How well does the side Touch ID work if you’re left-handed?

Ron Elemans:

The release notes of Xcode 27 RC doesn’t contain the phrase ‘Duo’…

Apple:

Learn how to update and optimize your app for the foldable display of iPhone Duo. Discover how to opt in to the full-screen experience, adopt flexible layout best practices, and simulate poses in Device Hub with Xcode. Find out how to use size classes instead of interface orientation, handle asymmetric safe areas, and test Split View multitasking to ensure your app shines in all the ways people use it …

Steve Troughton-Smith:

This is like a whole new platform dropping with a month’s lead time

Louie Mantia:

The app design implications alone that are now basically forced onto app developers is nuts. Vision Pro was opt in but… all iPhone apps have to support this new device right? What a nightmare. Ugh, websites? New safe areas?

Greg Pierce:

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Steve Streza:

As an anecdotal data point, I’ve had my foldable OnePlus Open for over 2 and a half years. It’s fallen on tile and cement, been kicked accidentally, and swatted across a room by my cat. The hinge and screens have no problems.

Imthaz Ahamed:

Here’s the list of tech products that have the Duo moniker[…]

Previously:

• iPhone 18 Pro and iPhone 18 Pro Max
• UIKit in iOS 27
• iPhone Air
• iPhone 18 Pro Variable Camera Aperture Rumor
• Galaxy Fold Review
• Galaxy Unpacked 2019

Update (2026-09-11): Tim Hardwick:

In a joint interview with Tom's Guide and TechRadar, new Apple CEO John Ternus and marketing chief Greg Joswiak explained why the company waited until now to release a foldable, its design philosophy, and how it kept the iPhone Duo under wraps.

Kelly Guimont:

So here are my biggest unanswered questions from yesterday:

They said the iPhone Duo will fit in a pocket and is great for one handed operation.

Whose hands?

WHOSE POCKETS!?

Juli Clover:

The iPhone Duo does not include an Action Button, according to the device’s technical specifications page.

Tim Hardwick:

“The iPhone Duo’s under-display camera wasn’t placed in the top-right corner of the inner screen because of engineering difficulties,” said the leaker in a Weibo post this morning.

Dan Moren:

In the end, every Apple product—and probably every product—is a story of trade-offs. So, the thinking went, what will we give up to get the benefit of a small iPhone that unfolds into a larger iPhone?

The answer: some things, but less than I’d feared.

Dan Moren:

The company’s view is clear: the iPhone Duo, even when open in all of its glory, may evoke an iPad, but it is very much not an iPad.

[…]

It’s not an iPad that you fold up to put in your pocket. Or an iPad with a little iPhone glued to the front. It’s not running iPadOS. You won’t be installing or running iPad apps.

Tim Hardwick:

Apple’s iPhone Duo is the first iPhone that can run two apps side by side, but anyone expecting the sort of freedom that Split View offers on iPad might want to temper their expectations.

Matt Birchler:

I’ve been using Samsung’s latest folding phone that has a very similar form factor to what Apple just announced, and it’s gotten me accustomed to what the folding phone experience is. I personally very much like it, and it’s the most joy an Android phone has brought me in close to a decade. That said, I just watched Apple’s iPhone Duo unveiling, and it immediately made my Samsung phone feel behind the curve.

Rui Carmo:

Most of the UX we saw so far was both predictable and familiar to anyone who’s played with a Samsung Z Fold (Apple did not invent screen splits, app swaps or drag and drop), and so was the camera placement.

Ruffin Bailey:

Imagine an iPad mini in your pocket. This is my dream!

Well, you had me in the first half; not going to lie. It’s a dream, but not at $2200.

[…]

Now admittedly part of me doesn’t trust the IP68 rating Apple claims for the Duo.

Juli Clover:

Apple says that you need the Apple Pencil with USB-C for the iPhone Duo, so if you have the Apple Pencil Pro, you may be out of luck.

John Gruber:

Charging is the least of the problems. Because the Duo doesn’t have the magnetic attachment for Pencil Pro, there’s no way to even pair a Pencil Pro.

[…]

Imagine you own an iPad Pro and a Pencil Pro, and you love using the Pencil. You’ve always wanted to be able to use a Pencil with your iPhone. Now you can, if you buy a Duo. But you also have to buy a different Pencil — and then pack two different Pencils whenever you leave the house with both your iPad and iPhone. That’s ridiculous.

Steve Troughton-Smith:

Also let’s not forget that the USB-C Apple Pencil doesn’t have pressure sensitivity, so the artists are already posting their disappointed reactions. I feel like this backs up that @markgurman report that they were planning on creating a bespoke Apple Pencil for the iPhone Duo that later got cancelled, and the USB-C version is the fallback.

Previously:

• Developing for iPhone Duo

Update (2026-09-14): Kirk McElhearn:

Folding smartphones are extremely popular in China: there are about as many foldables sold in China as in the rest of the world. Samsung, Google, Huawei, Motorola, Xiaomi, and other brands sell devices like this. Apple will likely sell a lot of devices in China, but given the reactions I’ve seen, they are poised to have a successful product elsewhere, in spite of the high cost.

[…]

For me, a folding phone would mean that for non-work tasks, I would have a larger display, not quite as big as my 11″ iPad Pro. I doubt I would do much work on it, but if I need to check my online accounting app or make a quick edit to an article on my blog, that larger display would be much more practical than my iPhone.

In addition, my eyesight isn’t great. Since the iPhone 8 was released with a larger screen size, I have always bought larger iPhone models. Even with that size, I need to zoom the text on my iPhone a notch above the standard size. A larger display for when I’m reading articles would be a help, not to mention a small, portable device that makes it easier to read PDFs.

Adam Engst:

I may not be the target audience, but I’m sure there are people who aren’t price-sensitive, spend a lot of time watching videos or playing games, and only ever carry their phones in a pocket or bag. But I don’t regularly encounter such people—I hear complaints about phones being too big, but never that they’re not big enough.

David Sparks:

I’ve made my choice. I’m buying the iPhone Duo instead of the iPhone 18 Pro Max.

Steve Troughton-Smith:

I do wonder whether iPhone Duo’s splitscreen multitasking mode will come back to iPad. People have been complaining all year that it went away, but it feels like Duo’s implementation is a simplified, easier-to-understand model. It might make sense to bring back in the future, especially for smaller iPads.

Update (2026-09-17): Riccardo Mori:

I really like the iPhone Duo. I like the hardware, the form factor, the construction, and how Apple has adapted iOS to work on this specific iPhone.

[…]

But, believe it or not, what makes the iPhone Duo unappealing to me is not the price. It’s not my diminished trust towards Apple as a company. It’s not even the fact that I’m slowly but surely abandoning the Apple ecosystem and don’t want another device that’ll pull me back in.

John Gruber:

The defining aspect of the Duo isn’t that it folds open and closed — we’ve seen almost a decade of Android phones that do that — but its aspect ratio, roughly 1.4 : 1. Because that’s effectively the square root of 2, doubling the outer display’s shorter dimension when you unfold it produces an inner display with roughly the same aspect ratio. That’s elegant and satisfying conceptually. And I think in practice it will feel right, too.

[…]

This aspect ratio is so different that it demands a different UI layout for the Duo to have any chance at being a good experience. That’s exactly what Apple has done, and what Steve Lemay was there in the keynote to unveil. A lot of UI chrome that previously was at the top or bottom of the display is now on the right — the dock on the home screen, the toolbars in apps, etc. And these elements are always on the right. You can’t turn the Duo upside down to move them to the left, nor is there an accessibility setting to move them to the left. This layout puts these controls on the right not because 90 percent of people are right-handed and Apple thinks lefties can get bent, but, I think (and so I’ve been told in conversations with Cupertinoites), because that’s the nature of a book-like shape.

[…]

I’ve only spent a few minutes, in total, playing with the Duo, so I really can’t say whether it succeeds or not. But I will say that it’s weird. Not saying it’s weird good or weird bad — just weird different. In some ways iOS on the Duo feels more different from iOS on all other post-iPhone-X phones than iOS on the original iPad felt from iOS on the iPhones of that time. The original iPad just felt like a much bigger iPhone. The Duo feels like a different layout entirely, in every single app that I had time to poke around with.

[…]

If you only have one display you don’t want it to be the size and shape of the Duo’s outer display. So the questions are: How tolerable has Apple’s UI redesign made it? And how will Duo users split their time between using it closed vs. using it open?

Update (2026-09-18): Hartley Charlton:

Apple’s design team reveals how notebooks helped inspire the iPhone Duo, along with interface principles and expectations for future features, in a new interview with GQ.

Update (2026-09-23): Imthaz Ahamed:

Apple is rightly celebrated for its accessibility work. So I’m left thinking the Duo’s locked layout is a v1 limitation, and that a future software update will offer orientation flexibility. But right now, Apple’s most ambitious new iPhone in years has shipped without it. A book-shaped iPhone should be able to accommodate the people holding it on either side.

Juli Clover:

Apple hardware engineering VP Tom Marieb spoke with TechRadar and shared some candid thoughts about Apple’s upcoming iPhone Duo.

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When asked if the iPhone Duo ‘s crease would be more visible over time, as that’s what tends to happen on other foldables, Marieb said the nano-texture display would help. He asked people to hold the company “accountable” on crease visibility.

Nick Heer:

Perhaps Apple would justify its USB 3.1 selectivity in reverse. The 10 Gbps transfer speeds capable with its recent Pro models are necessary for recording ProRes video to an external hard disk, after all, and professional video codecs are only available on the Pro model iPhones; ergo, those are the only iPhones that need a fast USB controller. But that is no longer an accurate reason, either, because there is now an iPhone which can do 10 Gbps USB transfers but has none of the professional camera technologies. It is the iPhone Duo. And that gives me hope that the rest of the iPhone line will catch up.

Michael Burkhardt:

That said, the company had initially planned to build a new Apple Pencil for the Duo. It would’ve been smaller and attached to the hinge side of the iPhone Duo.

According to Bloomberg, that pencil ran into “technical problems” prior to mass production, so the company scrapped it and went with the traditional USB-C Apple Pencil.

Apple A20 Pro Apple C2 Apple Event Apple Hardware Announcement Apple N1 Apple Pencil Camera iOS iOS 27 iOS Multitasking iPhone iPhone Duo StandBy Touch ID