Apple has entered the foldable smartphone market with the introduction of the iPhone Duo, its first iPhone with a foldable design, announced during the company’s latest Apple Event.

The book-style device opens to reveal a 7.6-inch Super Retina XDR display, the largest display Apple has placed on an iPhone. When folded, it uses a 5.4-inch outer display, giving users a more compact form factor while retaining access to the phone’s core functions.

Both displays support ProMotion and Always-On functionality, with up to 3,000 nits of peak outdoor brightness. Apple also says the inner display uses a nano-texture finish designed to reduce glare and reflections while making the fold less noticeable.

The device is powered by Apple’s new A20 Pro chip and uses a custom vapor chamber and dual-battery system for thermal management and battery capacity.

The foldable design also changes how the iPhone can be used for photography and video calls. The iPhone Duo features a 48-megapixel Fusion Main camera, a 48-megapixel Fusion Ultra Wide camera and an optical-quality 2x Telephoto capability.

Users can use the outer display as a preview when taking selfies with the rear cameras, while Duo Preview allows people being photographed to see the live camera framing.

Apple is also introducing Smart Take, which uses on-device AI to automatically capture photos when subjects are ready, as well as Duo FaceTime, which allows people on the other side of the device to participate in a call using the outer display and camera.

For video, the iPhone Duo supports 4K recording at 120 frames per second in Dolby Vision using its 48MP Fusion Main camera. Apple has also added features such as Cinematic effects that can be applied after recording and updated Audio Mix capabilities.

The larger inner display is also designed for multitasking. With iOS 27, users can open two apps side by side using Split View, run two windows of the same app and interact with Siri AI while viewing other content on the screen.

Apple says several third-party apps, including Netflix, Zoom and Slack, are being adapted for the foldable format.

The iPhone Duo is built with grade 5 titanium, uses Ceramic Shield protection and carries an IP68 rating for splash, water and dust resistance. Apple says its hinge uses more than 100 components to control the opening and closing of the device and support the center of the folding display.

Apple has also introduced Touch ID in the side button for authentication, while the device supports Camera Control and the new Siri Camera mode. Apple Pencil support through USB-C is expected later this year.

The iPhone Duo starts at $1,999 in the US for the 256GB model, with storage options reaching 2TB. It will be available in Star White and Night Sky. Pre-orders begin Oct. 16, with availability starting Oct. 23 in more than 70 countries and regions.

Alongside the foldable, Apple also unveiled the iPhone 18 Pro and iPhone 18 Pro Max, which bring upgrades focused on cameras, processing power, thermal management and battery life.

The Pro models introduce a 48MP Fusion Main camera with variable aperture, giving users manual control over four aperture settings while also allowing the camera to automatically adjust aperture based on lighting and depth-of-field requirements. Apple says the system can open to ƒ/1.48 for low-light photography and narrow to ƒ/4 for greater depth of field.

The iPhone 18 Pro lineup is powered by the A20 Pro chip, built using a 2-nanometer process, and includes a redesigned vapor chamber with three times the surface area of the previous generation. Apple says the thermal system can enable up to a 40 percent gain in sustained performance compared with the previous generation.

The phones also introduce an updated Dynamic Island, iOS 27, Apple Intelligence and a new Siri AI experience. The iPhone 18 Pro starts at $1,199 in the US, while the iPhone 18 Pro Max starts at $1,299. Pre-orders begin Sept. 12, with availability starting Sept. 18.

Together, the iPhone Duo and iPhone 18 Pro lineup mark Apple's latest push to expand the iPhone's hardware design while placing greater emphasis on larger displays, camera controls, sustained performance, and on-device AI.