Apple's first foldable phone, the iPhone Duo, has almost sold out at every retailer, with delivery dates now stretching into 2027, even ahead of its official launch. Tech critic David Phelan tested the device for weeks and describes it as a joy to use.
When open, the display measures 7.6 inches and has such thin bezels that it looks bigger than it feels. Folded, it is about the size and shape of a passport, fitting happily in a pocket, and it weighs almost exactly the same as the iPhone 18 Pro Max.
Design and displays
The iPhone Duo is both familiar and strikingly original. The home screen dock of four icons now sits vertically on the right edge, not at the bottom, due to the wider, shorter display. A circular icon showing battery life, Wi-Fi strength and cellular connectivity sits below the corner-mounted front-facing camera.
Unlocking uses Touch ID, mounted in the side button similar to the iPad Air, rather than Face ID. Apple used Touch ID to give consistency to the unlocking process whether the phone is open or closed. The build quality includes a titanium frame, scratch-resistant Ceramic Shield 2 on the front, and the original drop-resistant Ceramic Shield on the rear. The hinge can be adjusted to stay in multiple positions, allowing StandBy view to activate even when the phone is unplugged.
Both displays are OLED. The outer screen matches the pixel density of the iPhone 18 Pro and iPhone 18 Pro Max at 460 pixels per inch, while the inner screen is 430ppi. The inner screen has a nano-texture finish, meaning no reflections and fingerprints don't show up, and the crease is completely invisible thanks to supporting plates and other materials.
Cameras and performance
There are two rear cameras on the iPhone Duo: a main and an ultra-wide, both with 48-megapixel resolution. The main camera can achieve a 2x optical zoom equivalent by cropping to the central portion of the sensor, dropping resolution to 12 megapixels. There is no telephoto camera and no adjustable aperture.
When taking someone's photo, you can let them see themselves on the front screen and pose accordingly. A feature called Kid Cue plays a series of cartoons starring Snoopy to attract the attention of your subject.
The Duo has the same fast processor as the iPhone 18 Pro. Battery life manages a full day but definitely needs an overnight charge.
Apps and verdict
App developers are updating their apps for the new screen real estate. Instagram, Threads and Facebook were Duo-optimised in one day alone, and key apps including Netflix, Sonos and Slack are also ready to go. Apple has introduced software unique to the Duo that allows an open app to be placed on the right or left side, with a second app filling the rest of the display.
The iPhone Duo is not perfect; it takes a little getting used to, and it's expensive. But using it is a revelation, with the joy of extra screen real estate in a pocketable phone. The invisible crease is better than on other foldables, and the hinge adjusts perfectly to different shapes. The only real absences are the telephoto lens and Face ID. The Duo is effortlessly seductive and, in time, is likely to be the product that takes foldable phones mainstream.
