iPhone Duo: Apple finally folds the iPhone, and it is John Ternus's first bet

Apple has finally done what it had been putting off for seven years: it folded the iPhone. On September 9, at the “Surprise and Shine” keynote, John Ternus introduced the iPhone Duo, the first foldable iPhone in history, at $1,999 and €2,339 in France. The moment carries double weight. It is the first new iPhone category since 2007, and it is the very first keynote by Tim Cook's successor, who took over Apple eight days earlier.

1. What the iPhone Duo looks like

Picture an iPhone slightly narrower than usual that opens like a small notebook. Closed, it fits in a pocket and shows a 5.4-inch screen, barely smaller than an iPhone 18 Pro's. Open, it unfolds a 7.6-inch panel, one and a half times the surface of an 18 Pro Max. Both screens share exactly the same proportions, so a video or a web page moves from one to the other without being recropped.

The most discussed number is the thickness. Open, the device is just 5.2 mm thick, making it the thinnest iPhone ever built, ahead of the iPhone Air. Folded, it naturally doubles up and weighs 254 grams, slightly more than a Pro Max. The frame is titanium, the hinge counts more than a hundred parts, and the device is water resistant.

Beyond that, it is a fairly conventional high-end iPhone: the same chip as the 18 Pro, two batteries instead of one (one per side) that comfortably last the day, and two 48-megapixel cameras. The most visible novelty is on the software side. For the first time, an iPhone can show two apps side by side, or two windows of the same app, and remember those pairings. Pre-orders on October 16, deliveries on the 23rd (MacRumors).

2. John Ternus's first launch

It is hard to read this announcement without its context. Tim Cook stepped down as Apple's chief executive on September 1, after fifteen years, to become executive chairman of the board; the transition had been made public on April 20 (Apple). His successor, John Ternus, is an engineer who joined Apple in 2001 through product design and who until now ran the entire hardware side of the house: iPhone, iPad, Mac, Watch, Vision Pro.

Apple's new boss therefore opens his tenure, eight days into the job, with an entirely new form factor. His press-release line sets the intended tone: “iPhone Duo is the most transformational change to iPhone since the original.” Several observers noted the symbolism: a hardware executive choosing to open his tenure with an object, at a moment when the industry is being fought over on artificial intelligence.

3. Duo or iPhone 18 Pro: what separates them

The two devices share the same chip but not the same brief. At €2,339 against €1,479, the Duo costs €860 more, and the point-by-point comparison takes up much of the commentary published since the announcement (The Mac Observer). What the foldable does not have:

no dedicated telephoto. The “optical-quality 2×” Apple announced is a crop inside the main image, whereas the Galaxy Z Fold 7 already carried three lenses last year;
no Face ID. Face recognition gives way to a fingerprint reader built into the side button, for lack of room inside 5.2 mm;
no SIM tray and no aperture control, reserved for the 18 Pro. The Duo runs on eSIM only;
slightly less battery life on the big screen, and five extra weeks of waiting before availability.

Conversely, the Duo offers what no other iPhone does: a 7.6-inch screen, two apps displayed at once, the ability to stand the device open like an easel and shoot yourself with the rear cameras, or record front and back at the same time (PetaPixel). Digital Camera World, which calls the photographic trade-off “confusing,” draws a conclusion that applies to the whole range: there is no single “best iPhone” any more, every model imposes its own trade-off.

4. The question of the crease

It is the first thing anyone looks for on a foldable. Apple's answer is the nano-texture finish applied to both screens, presented as an anti-glare treatment that also reduces the visibility of the fold, to the point of making it “virtually imperceptible” according to the company (PetaPixel). The subject was not dwelt on at length on stage, however.

The tech specs mention neither a rated number of openings nor a crease depth, two figures some competitors publish. It is also the part that weighed most on the schedule: mass production only started in July, once the hinge manufacturing difficulties had been resolved (TrendForce). The first independent durability tests will provide the answer.

5. Meanwhile, the iPhone 18 Pro

Overshadowed by the foldable, the iPhone 18 Pro and Pro Max bring the year's most concrete improvement for anyone who likes taking pictures: a variable aperture. Until now, an iPhone lens always let in the same amount of light. This time a genuine mechanical iris opens and closes, just like on a camera. In practice, you pick for yourself between a nicely blurred background and an image that stays sharp from the foreground to the horizon, instead of letting software fake the effect.

Apple also introduced Apple Reference Image, which signs photos in a way that cannot be forged: at a time when any AI turns out a believable picture in seconds, the iPhone supplies the proof that a photo really is a photo. As for the rest: much improved cooling, a big jump in battery life, a new burgundy finish, €1,479 and €1,629, on sale September 18 (Apple). iOS 27 lands on the 14th, with the new Siri in beta, English first and French from October (Engadget).

6. A slimmer autumn line-up

The big absentee from the keynote is the plain iPhone 18. Apple now spreads its calendar across two seasons: Pro models and the foldable in the autumn, then the iPhone 18, iPhone 18e and iPhone Air 2 in spring 2027 (MacRumors). The original iPhone Air, released in September 2025, sold less well than hoped.

The consequence is direct: the autumn line-up now starts at €1,479, and the more affordable models of this generation will not arrive until next spring.

7. What the leaks had anticipated

On this front, the record speaks for itself. Bloomberg's Mark Gurman gave the “iPhone Duo” name hours before the keynote, while the specialist press was still running “iPhone Ultra” headlines that very morning (The Apple Post). He also had the $2,000 price, both colours and Apple Pencil compatibility, duly announced for later this year.

Ming-Chi Kuo aimed higher on price: he called $2,300 to $2,500 and judged demand solid at that level, while research firm IDC suggested “$2,500 or more.” Apple positioned itself well below. His other forecast holds up better: he described a “repeat of the iPhone X,” meaning a headline announcement, a delayed on-sale date and tight stock through the end of the year. The October 23 date points that way (MacRumors).

8. How the market is receiving it

The pricing has been widely discussed: at $1,999, the Duo lands exactly on the Galaxy Z Fold 7's tag rather than going below it. Analysts read that differently. KeyBanc, one of the very few desks advising clients to sell Apple stock, saw the event as “likely a negative catalyst,” while Bank of America reckons the reaction will hinge mostly on how the new Siri is received and on early demand signals (Yahoo Finance).

Sales forecasts also vary widely. Counterpoint expects 6 million units in 2026, which would make Apple the number two in foldables in its first year; IDC suggests 10 million instead, while recalling that foldables will account for just 2.2% of smartphones sold in 2026. Worth noting, finally, that the screens in Apple's foldable come out of Samsung Display factories, its exclusive supplier for three years (DigiTimes).

The bottom line: the iPhone Duo is the iPhone's first change of form factor since 2007, with deliberate technical choices: a large screen and genuine multitasking on one side, no telephoto and no Face ID on the other, for €860 more than an iPhone 18 Pro. Two unknowns will stay open until the first reviews: how the hinge holds up over time, and how much appetite there is for a format that still represents a small share of the market. To gauge what is at stake, remember that the team that designed the Vision Pro now works at OpenAI, on the device meant to replace the iPhone.