Apple’s first foldable, the iPhone Duo, is a $1,999 device that asks buyers to accept first-generation compromises in exchange for a genuinely new iPhone experience. It uses a wide, passport-style shape, a small outer screen, and a larger inner display with a matte finish. Testing found it fun and surprising but also bulky, expensive, inconsistent, and prone to heat. The device is clearly aimed at early adopters rather than people who want a simple, predictable upgrade.

Key facts at a glance

• Price: starts at $1,999.
• Form factor: book-style foldable with a wide 1.4:1 aspect ratio on both displays.
• Displays: 5.4-inch glossy cover screen; 7.6-inch inner screen with nano-texture matte coating.
• Security: Touch ID in the side wake button; no Face ID.
• Chip: A20 Pro with vapor chamber thermal management.
• Durability: IP68 water and dust resistance; MagSafe support.
• Cameras: no telephoto; 48MP ultrawide; 12MP Center Stage selfie; low-resolution under-display FaceTime camera.
• Software: requires Duo-specific iOS 27.1 updates for best results; many apps remain unoptimized.
• Battery: heavy use required at least one charge during a workday.
• Main competitor: Samsung Galaxy Z Fold 8.

A wide passport-style design

Apple’s most important design decision was to make the Duo shaped like a passport. The wide aspect ratio makes the inner screen friendlier for 16:9 video, but it departs from the tall-and-narrow foldable shape that phone makers embraced for years. Before 2026, most folding phones were optimized for vertical apps on the cover screen. The Duo flips that priority, and competitors began shifting toward wide formats as rumors about Apple’s plans circulated. The result is a new problem: how to design a cover screen that works well enough for vertically oriented apps.

The outer display is 5.4 inches and glossy. The inner display is 7.6 inches and has a striking nano-texture matte coating. Apple is proud of the matte inner screen, and the finish does look and feel solid. It is a step up from glossy foldable screens with obvious creases. The matte coating is meant to hide the crease, which Apple calls perceptually flat. The description is marketing language, but it is mostly accurate: the crease is hard to see, though it can still be felt. It becomes visible on white images viewed off-axis, in some lighting, and more often on camera than to the eye. The under-display camera also reflects light in a glossy way outdoors or in bright areas. After a week of constant folding, the crease did not become more noticeable, but long-term durability remains an open question.

Duo owners will flip the phone open constantly. Between the display aspect ratio and iOS design choices, the outer screen feels more like a status display than a primary screen. Everything nudges users to open the device and use it in tablet mode—specifically portrait tablet mode. iPhone apps are largely portrait, and the Duo is still an iPhone even though its shape fights that history. iPhones have grown taller over time, from 2:3 early models to 16:9 and then 19.5:9. The Duo is the first iPhone to get shorter and wider. Both displays share a 1.4:1 aspect ratio, a deliberate choice that makes the screens the same shape open and closed. It is clever for display math and potentially useful for developers, but in practice the outer display is quite small. With the keyboard open in Messages, users are lucky to see two or three texts at once.

Apple has moved UI elements in updated apps to the right to reclaim vertical space. That helps right-handed users but makes left-handed one-handed use challenging. The strip of navigation controls on the right also forces right-handed users to reach farther for left-side targets. Users sometimes hold a heavy phone while stretching for a small target just out of reach. The control layout is disorienting in other ways. In Mail, the back button moves from the top left to the right. Much of the Duo experience involves relearning how to use an iPhone. Apps that are not updated show a black bar on the right side of the cover screen where navigation controls would otherwise live. Even updated apps often feel useful only for quick checks.

Apple says the cover screen offers 90 percent of the screen area of an iPhone 18 Pro, but that still feels small for modern apps. It is like having an iPhone 5 in a world of Pro Max phones. When users pull the Duo from a pocket, they see a tiny amount of information. The moment they want to do anything, they unfold the phone. Opening the Duo does not add height. Switching from a small portrait display to a larger landscape view is not useful for most phone apps, which are designed around big portrait displays. Standard iPhone apps look normal but with black padding on either side. The experience is either cramped on the outer screen or awkward on the inner screen. Users instinctively rotate the phone, and rotating counterclockwise works better so cameras are on top and volume buttons are on the top left. The gesture starts to feel natural after a week, but it is the opposite of what people expect. The bumper case has a large notch for Touch ID and camera control, and it looks like it belongs at the bottom.

Volume controls create another adjustment. When closed, the buttons are on top. Rotate clockwise and they end up on the bottom right. The top button turns volume down because the buttons do not change orientation with the display. A buried iOS setting can make the volume buttons reorient themselves, but Apple should enable correct behavior by default. Unlocking is also different. Touch ID is integrated into the side wake button. There is no Face ID. Users may stare at the phone and wonder why notifications are not unfurling. A week is enough to get used to Touch ID again, and it becomes mostly painless.

The chaos is also fun. The iPhone has been the same for so long that learning small moves, tricks, and ways to hold the Duo is a thrill for gadget nerds. Other foldables have pushed similar boundaries, but Apple has played it safe for years. The Duo is genuinely surprising. Apple has not found a magical software solution that makes a complex product less chaotic. It is the kind of first-generation chaos that delights early adopters and sends most other buyers back to regular iPhones.

Software and app support

The first-generation wonkiness is most obvious in software, especially third-party app support. Many people assume the Duo simply opens into an iPad, but it does not work that way. Apple threw out the iPad approach and started over. That removes some iPad baggage but brings back problems the iPad had already solved. The Duo does not support pinching the keyboard to make it smaller for one-handed use, a feature iPads have had for years. Multitasking is also new and sometimes unpredictable. Apps interact with iOS and each other in different ways, so users are not always sure what will happen when they swipe around.

To run two apps at once, users swipe up and over to pin an app to one side, then pin another app to the other side. Tapping the divider connects the apps into a set that can be restored from the app switcher. The feature is neat but only works in landscape. In portrait mode, two apps are basically unavailable unless the user wants video on top and another app on the bottom. That requires an app with background video support: open the video app, start the video, close the app to initiate a floating video window, open the second app, then find a small button in the floating window and tap it to arrange everything. It is legitimately cool once figured out, but it is a totally different approach from any previous iPhone or iPad. Nothing about the interface makes the feature obvious. Some features work only in some apps some of the time. Floating video works with YouTube TV but not regular YouTube, which is surprising because the YouTube app appears at least partly updated for the Duo.

There are basically three ways apps work on the Duo. First, regular iPhone apps that have not been updated at all. They can be zoomed and rotated as on an iPad, but they look silly. This is the vast majority of apps, though more were updated during testing. Second, apps updated for iOS 27 get some automatic layout fixes. They expand to fill the inner screen in landscape and look less silly than standard iPhone apps. But they were not actually designed for the displays, and rough edges are obvious. Their telltale sign is the black bar on the right of the cover screen. Proper Duo apps add controls to that space; in-between apps do not. Third, fully updated apps built for Duo-specific iOS 27.1 can be quite good. Instagram’s Edits app is a strong example: it opens into a full video editor with a big timeline and preview window. Slack moved from the messy middle to fully updated during the testing period, which made a big difference on the inner screen. But none of that fixes the small outer screen.

Developers will need energy to create useful experiences or encouragement from Apple, or both. Some apps show what is possible. Deck-Man reformats Apple Music into a little virtual Walkman. The page-turn animation in Books is terrific. PDFs look particularly good on the matte display, especially for reading on a big screen in the back of an Uber. Still, users will see many tiny iPhone apps and many apps in the unoptimized middle zone for a while. The situation is messy in some of the same ways Android foldables are messy. That is surprising because Apple had an ecosystem of iPad apps ready. For whatever reason, the company did not go that way, so the Duo’s app story will take time to settle.

Versus the Samsung Galaxy Z Fold 8

Source: The Verge News