iPhone Duo pre-orders open Friday at 5 a.m. PT, starting at $1,999

Pre-orders start Friday at 5 a.m. Pacific, which is 8 a.m. Eastern, on apple.com and in the Apple Store app. The phone itself arrives a week later.

Here is the timeline:

• September 10: Apple unveiled the iPhone Duo.
• Thursday, October 15, 9 p.m. PT: the deadline to save your choices to your shopping bag for one-click checkout.
• Friday, October 16, 5 a.m. PT: pre-orders open.
• Friday, October 23: the phone is available.
• Friday, October 30: it reaches 28 more countries and regions, MacRumors reports.

The first wave of countries includes the US, Canada, the UK, France, Germany, Japan, China, India, Australia, Brazil, Mexico, South Korea, Singapore and the UAE, among others, according to MacRumors.

In real life Open the Apple Store app tonight, pick your color, storage and trade-in, and save it all to your bag before 9 p.m. PT. At 5 a.m. Friday, you just tap once.

It costs a lot more than a regular iPhone. MacRumors lists the US prices:

By the numbers: the jump from the base model to the top model is $1,200. That is the price of a whole second phone just for extra storage.

It folds like a small book. Closed, it is a compact phone. Open, it is close to a small tablet.

"iPhone Duo is the most transformational change to iPhone since the original," Apple CEO John Ternus said when the phone was unveiled in September.

• Inner screen: 7.6 inches, which Apple says is 50 percent larger than the iPhone 18 Pro Max.
• Outer screen: 5.4 inches, with 90 percent of the screen area of the iPhone 18 Pro.
• Thickness: open, it is the thinnest iPhone ever, Apple says.
• Chip: the new A20 Pro, with a vapor chamber for cooling and a dual-battery design.
• Build: grade 5 titanium and an IP68 rating for water and dust.
• Unlocking: Touch ID in the side button, so it works the same open or closed.

Both screens share the same shape, so apps simply scale up when you open the phone. Apple also says a matte nano-texture finish on the inner screen cuts glare and makes the crease harder to see.

This is the question everyone asks about foldables. Apple says the hinge is built from more than 100 components and supports the middle of the screen so it lies flat when open.

The inner screen has a scratch-resistant coating and a cover layer made from a custom polymer. Apple says it is up to 40 percent stiffer than materials used elsewhere in the industry. Glass sits above and below the folding panel, and the layers slide past each other like pages in a book to ease bending stress.

On the outside, Ceramic Shield 2 offers 3x better scratch resistance than the previous generation, according to Apple.

Split View lets you run two apps side by side on an iPhone for the first time. You can also open two Safari windows to compare prices, or keep Siri open next to an app and ask about what is on screen.

iOS 27 changes its layout for the Duo. Content reacts as the phone folds, turns when you rotate it, and jumps to the right screen when you flip it over. MacRumors reports the phone ships with iOS 27.1.

StandBy works on either screen, even when the phone is not charging. Set it down half open and it becomes a clock, a photo frame or a widget hub.

Apple says apps like Netflix, Zoom and Slack already use the larger screen. Zoom, for example, can show a shared screen and the people on the call at the same time.

The cameras:

• 48MP Fusion Main: zero shutter lag and an optical-quality 2x zoom.
• 48MP Fusion Ultra Wide: the same one as on the iPhone 18 Pro, with macro photos.
• Center Stage front camera: takes landscape selfies without turning the phone.
• Under-screen FaceTime camera: hidden beneath the inner screen for video calls with the phone open or propped up.

Apple also says Apple Pencil with USB-C support is coming to the Duo later this year.

Siri AI, the new version of Siri powered by Apple Intelligence, is rolling out in beta in English with iOS 27. Apple says it is more useful on the big inner screen, where you can keep Siri open next to an app.

Two cases and a lot of ways to pay.

• iPhone Duo Folio: navy blue or taupe, with a built-in kickstand for reading, watching or FaceTime.
• iPhone Duo Case: sand or navy blue, thin and light, with a two-part design that wraps both halves.
• Charging: both cases work with MagSafe, Qi2 25W and Qi chargers.

The payment options:

• Trade-in: $175 to $885 in instant credit for an eligible iPhone 13 or newer.
• Lease: Apple Upgrade, provided by Klarna, starts at $57.99 a month on a 24-month lease, before taxes and trade-in. At the end you can upgrade, buy it out or return it.
• Carrier deals: up to $1,200 in credit with AT&T, T-Mobile or Verizon when you trade in an iPhone 14 Pro Max or newer.
• Apple Card: 0 percent APR monthly installments and 3 percent Daily Cash in the US.
• Bonus: new and qualified returning subscribers get three months of Apple One free.

Protection plans: AppleCare+ covers drops and spills, and in many regions theft and loss too. AppleCare One Individual extends the same coverage to two more devices at the same monthly price, and US buyers can pick AppleCare One Family for every eligible device in a Family Sharing group.

Apple is also adding Today at Apple sessions in its stores, including "Say Hello to iPhone 18 Pro and iPhone Duo," for people who want a hands-on tour.

Why it matters: Apple is putting almost as much effort into how you pay for the Duo as into the phone itself. At $1,999 and up, the lease and trade-in deals are how many people will actually afford one.

Possibly. Reports last month said Apple planned to make only 6 to 8 million iPhone Duo units this year, well below a normal flagship. Apple has not confirmed those numbers.

What's next: if early demand outruns supply, delivery dates could slip quickly after Friday morning. Apple's own advice is to set everything up ahead of time. For more Apple news, see our Apple topic page.

• Prepare tonight: save your configuration and trade-in to your bag before 9 p.m. PT Thursday for one-click checkout.
• Check your old phone: an iPhone 13 or newer earns $175 to $885 in trade-in credit, and carriers offer up to $1,200 for newer Pro Max models.
• Think about storage: each step up costs $200 to $600 more, so pick what you will really use.
• Budget for a case: the Folio's kickstand makes the most of the big screen on a table.