On 9 September 2026, Apple announced iPhone Duo, its first foldable iPhone. In Japan and more than 70 other countries and regions, pre-orders began at 9:00 p.m. JST on 16 October, with sales starting on 23 October.
Opened, the inner display is 7.6 inches. Closed, the outer display is 5.4 inches. Both share the same aspect ratio. The chip is the same A20 Pro as iPhone 18 Pro. In Japan, pricing starts at 364,800 yen including tax, with 256GB, 512GB, 1TB, and 2TB storage.
This article sticks to Apple’s public announcement and lists what companies with apps or web services should check before launch day.
When it goes on sale, and for how much
Apple’s Japan newsroom says pre-orders start at 9:00 p.m. JST on 16 October and sales start on 23 October. Another 28 countries and regions start sales on 30 October. Colors are Star White and Night Sky. The case is 14,800 yen and the folio with a stand is 24,800 yen, both including tax, with orders from 16 October.
SoftBank takes pre-orders from 9:00 p.m. on 16 October and sells from 23 October. Rakuten Mobile’s official site and Rakuten Ichiba store take pre-orders from 9:00 p.m. on 16 October and start sales at 8:00 a.m. on 23 October.
What changed in the hardware
Apple says the 7.6-inch inner Super Retina XDR is 50 percent larger than iPhone 18 Pro Max, while the 5.4-inch outer display covers 90 percent of iPhone 18 Pro’s screen area. Both use ProMotion and an always-on display, with up to 3,000 nits outdoors. Apple Pencil (USB-C) support is planned later this year.
The body is grade 5 titanium. The hinge has more than 100 parts. The phone is rated IP68. Ceramic Shield 2 on the front is described as three times more scratch-resistant than the previous generation. A20 Pro is built on a 2-nanometer process, with up to 20 percent faster CPU than A19 Pro and up to 40 percent faster GPU. Video playback is quoted at up to 31 hours on the inner display, 44 hours on the outer display, and 24 hours when both are used about equally.
How apps are expected to work
iOS 27 moves controls to the sides to keep more vertical space. Opened, the home screen becomes two pages, with a scrolling Today View on the left. Split View can place two apps side by side for the first time on iPhone, including two Safari windows. Apple says Netflix, Zoom, and Slack already use the larger canvas. Developers can adapt apps with the latest SDK APIs and Xcode’s device hub.
What to check in your own app
A foldable is not only a bigger phone. Work should continue when the user opens or closes it. Signup, booking, chat, and admin lists should not lose input or push buttons off-screen when the canvas changes.
- Spacing, buttons, and tables on the large canvas
- In-progress input surviving Split View
- Camera and calls in both open and closed states
- Primary actions still reachable in portrait and landscape
iPhone Duo is eSIM-only worldwide. Instructions that assume handing over a physical SIM card need a rewrite. Apple says eSIM works with carriers including au, NTT Docomo, and SoftBank.
Camera and on-device AI
The camera system includes 48MP Fusion main and ultra-wide cameras. Fold-specific ideas include selfies with the rear camera previewed on the outer display. Siri AI arrives as a beta in iOS 27, including conversation beside on-screen content. Apple still describes a mix of on-device processing and Private Cloud Compute.
If you add generative AI to your own service, do not assume the new phone can hold every workflow. Decide where customer and booking data is processed, and who checks the result. A large screen is useful for showing an answer next to the source, which also means the UI should make that check easy.
Summary
iPhone Duo pre-orders began on 16 October 2026, with sales on 23 October. The practical points for app owners are the paired 7.6-inch and 5.4-inch displays, Split View, and eSIM-only setup. Pricing in Japan starts at 364,800 yen including tax. Primary source: Apple’s newsroom.
Makoto Tejima builds iOS and Android apps together with the web systems behind them. Contact us if you want an existing app reviewed for a larger canvas, or a new member, booking, or business app.