iPhone Duo Is Apple's Foldable, and iOS Had to Move Sideways to Fit It
Apple's first folding iPhone lands on the same passport shape Samsung just adopted, but the bigger change is an interface that now lives along the edge of the screen.
Apple announced iPhone Duo on 9 September, its first foldable phone, alongside the iPhone 18 Pro and iPhone 18 Pro Max. The Duo has a 7.6-inch inner display and a 5.4-inch outer one, both with the same aspect ratio, and starts at $1,999 in the US with storage from 256GB to 2TB. Pre-orders open on 16 October and the phone ships on 23 October, running iOS 27.1. The 18 Pro and Pro Max start at $1,199 and $1,299 and arrive on 18 September. John Ternus, quoted in the release as Apple's chief executive, called the Duo the biggest change to the iPhone since the original.
A familiar shape, chosen on purpose
Seven weeks after Samsung introduced a wider Galaxy Z Fold 8 with a 7.6-inch, 4:3 inner screen, Apple has arrived at almost the same answer. Apple describes the closed Duo as similar in size to a passport. The outer display gives 90 per cent of the screen area of an iPhone 18 Pro; opened, the inner display is 50 per cent larger than the 18 Pro Max.
The decision that matters most is the shared aspect ratio. Because both screens have the same proportions, content scales rather than reflows when the phone opens. That is a quieter idea than a hinge or a crease claim, but it removes the most jarring moment in most foldables: the app redrawing itself into a different layout mid-gesture. It also simplifies life for developers, who are designing one composition at two sizes instead of two compositions.
The hardware choices follow from the shape. Unlocking moves to Touch ID in the side button, so it works the same whether the phone is open or closed. The inner FaceTime camera sits beneath the display. The inner panel gets a nano-texture finish that Apple says reduces glare and makes the crease less visible, which is a candid admission that the crease is still there. There is no dedicated telephoto: a 48-megapixel main camera crops to an optical-quality 2x, paired with a 48-megapixel ultra wide.
The interface is the real redesign
The most radical part of the announcement is iOS 27 on the Duo. Lock Screen controls, the Dock and in-app navigation move to the side of the screen to give content more vertical space. The Dynamic Island is redesigned to sit vertically along the side of both displays. The status bar becomes a circular cluster tucked into a corner. When the phone is open, the Home Screen shows two pages at once with Today View, a scrolling column of widgets, on the left.
Moving the chrome to the edge is the right call for a wide screen. On a wide panel, height is the scarce dimension, and stacking a status bar, navigation bar, content and tab bar vertically wastes it. Tablets and desktop apps solved this with sidebars years ago. What is notable is Apple doing it on an iPhone, where the top-and-bottom convention has held since 2007. It will be interesting to see whether side-docked controls stay a Duo exception or drift into other devices.
The risk sits with third-party apps. Apple says Netflix, Zoom and Slack have already adapted, and promises new APIs and Duo support in Xcode's Device Hub. The long tail of apps that hard-code a top navigation bar will look out of place until they catch up.
The 18 Pro, briefly
The Pro phones are a conventional year done well. The headline is a variable-aperture main camera with six blades, ranging from f/1.48 to f/4. A20 Pro, built on a 2-nanometre process, places memory beside the die rather than on top of it so the chip can contact a vapour chamber with three times the surface area, which Apple credits for up to 40 per cent better sustained performance. The Dynamic Island shrinks and can show three Live Activities at once. A new Reference mode signs sensor data so a photo can be compared against what the camera actually captured, which may prove the most consequential feature of the year.
What is still unknown
- Durability in the wild. Apple describes a hinge built from more than 100 components and a layered display stack designed to relieve bend stress. Only a year of pockets will say how well it works.
- Price positioning. At $1,999, the Duo is $100 above Samsung's wide Fold. Apple is betting that the software work justifies the gap.
- Apple Pencil. Support is promised later this year, which would make the Duo a small sketchbook as well as a phone.
Sources