The best apps for iPhone Duo: 10 with confirmed support

iPhone Duo goes on sale on 23 October 2026, and it changes what a good app looks like. Apple says apps built with the iOS 27.1 SDK use the full display, with tab bars and toolbars down the side. Apps built with the iOS 26 SDK or earlier sit in the middle of the open screen with empty space around them. So the useful question is which apps their makers have actually rebuilt.

We have not used an iPhone Duo, and on 9 October nobody could buy one yet. So this list does not score how the apps feel in the hand. It ranks what each maker has put in writing, and it shows each app's real App Store rating. A disclosure: we make Chonky Corgo. It is #2 because we put it there, and its entry says plainly what it does not do yet.

Which apps support iPhone Duo right now?

Ten apps have a primary source behind them on 9 October 2026. Detail, Agenda and Overcast say it in their own App Store release notes. Apple's iPhone Duo announcement names Netflix, Zoom and Slack. Apple's design guidelines and product pages describe Mail, Notes and FaceTime. Chonky Corgo, our game, has its iPhone Duo layouts in testing.

How did we rank the 10 apps?

An app made the list only if its maker or Apple says in writing that it works with iPhone Duo. We ordered them by how much of the device that source describes, like the fold or outer screen, and by whether that version is out today. Number 2 breaks the rule: it is our game, and we chose its place.

What are the best apps for iPhone Duo?

Here are the ten, each with its real App Store rating and our short take. The takes are ours, based on what each maker documents rather than on hands-on use. The ratings cover the iPhone app in the US store, so they describe the app on every iPhone, not on iPhone Duo alone.

1. Detail: AI Video Editor

Detail's 9 October update is the most complete iPhone Duo release note we found. Detail records with all three cameras: outer, inner and rear. With the phone open, Flip Cameras cycles through all three. While you film yourself with the rear camera, Detail can show your live preview and your teleprompter script on the outer screen, right by the lens. A new Book Mode records the outer and rear cameras together in a split screen. Apple also names Detail in its iPhone Duo announcement, for running its AI models on the device. The catch is simple: all of this is for people who make videos.

Rating: 4.6 from 3,859 ratings. Price: free, with in-app purchases.

2. Chonky Corgo (ours)

Chonky Corgo is our walking RPG: your daily steps from Apple Health charge attacks on pixel monsters and move a story forward. Our iPhone Duo update, version 2.1, was in testing on 9 October and was not on the App Store that day. In that build, the open phone held sideways shows two pages side by side, such as the battle beside your day or Chonky's room beside its list, and a screen with one page gets a window onto Chonky's town, Pawville. Playtime has 11 small toys you play by folding the phone, and rewards in the inbox open in a treasure chest whose lid follows the hinge. On other iPhones the toys use a slider.

Here are the weaknesses, plainly. The App Store version today is 2.0.0, released on 30 September, before Apple accepted iPhone Duo builds, so it does not use the full open screen. Chonky Corgo has no App Store ratings yet. Signed-in players 18 and older see one small banner ad until they turn it off in Settings or buy No Banner Ads. To see how it stacks up as a walking game, our comparison of walking apps like Pokemon GO gives it a row, weakness included.

Rating: no ratings yet. Price: free, with in-app purchases (Chonky Club, No Banner Ads and Gems).

3. Agenda: Notes meets Calendar

Agenda's 8 October update, version 23.4, opens with 'Agenda is ready for iPhone Duo.' With the phone closed, Agenda's buttons move into the side column next to the status bar, which is where Apple puts its own. Half open, the sidebar and your notes sit on each side of the fold. That is the layout Apple's guidelines ask for, and it suits an app that ties each note to a date. Agenda's notes do not say what happens when the phone lies fully flat.

Rating: 4.6 from 3,682 ratings. Price: free, with premium features through a yearly subscription or a one-time lifetime purchase.

4. Mail (Apple)

Mail is Apple's own example of the basic iPhone Duo idea. Apple's design guidelines say that with the phone closed, Mail shows either your list of emails or one email. Open, Mail shows both side by side. Apple's iPhone Duo page also shows Mail in Split View, with a picture dragged in from Photos. Mail is already on the phone, so there is nothing to install. Apple documents nothing beyond the side-by-side view, so do not expect anything clever with the hinge.

Rating: 4.6 from 4,494,409 ratings. Price: free and built in.

5. Notes (Apple)

Notes gets one sentence in Apple's guidelines, and it is the right one: the Notes split view adjusts the width of each pane so both stay clearly visible as the device folds. Your list stays on one side, your note on the other, and neither ends up in the crease. The guidelines also use New Note as their example of an action to keep visible when controls run out of room. Apple documents nothing for Notes on the outer screen.

Rating: 4.8 from 652,380 ratings. Price: free and built in.

6. FaceTime (Apple)

FaceTime has the most social trick on the device. Apple says Duo FaceTime lets someone nearby join the call using the outer display and its camera. Apple also says the FaceTime camera under the inner display works for calls with the phone open or propped up. The trick only helps when someone is in the room with you, and FaceTime's 4.2 average is the lowest of Apple's three apps on this list.

Rating: 4.2 from 27,142 ratings. Price: free and built in.

7. Netflix

Apple names Netflix as one of three third-party apps already using the folding design. In Apple's description, you scroll through Netflix Clips on the outer display and watch on the large inner screen. On a phone that opens to a 7.6-inch display, a video app is an obvious first install. Netflix's own release notes do not mention iPhone Duo yet, so Apple's announcement is the only source, and watching needs a paid Netflix membership.

Rating: 4.7 from 7,408,034 ratings. Price: free download, with a month-to-month membership to watch.

8. Slack

Apple's announcement says that on iPhone Duo, the Slack app brings a user's whole workspace into view. Apple says no more than that, and Slack's own release notes do not mention iPhone Duo yet. Slack's 4.1 average is the lowest of the rated apps here, and the listing says some features need Slack Pro, Business+ or Enterprise.

Rating: 4.1 from 53,226 ratings. Price: free, with some features on paid Slack plans.

9. Zoom Workplace

Apple says the Zoom app can turn the inner display into an immersive video conference room, with shared content and participants on screen together. That is the clearest work use for the big screen on this list. But Zoom's current App Store version, 7.2.1, is dated 28 September, a week before Apple started accepting iPhone Duo apps on 5 October. So the layout Apple showed is not confirmed in the version you can download today.

Rating: 4.7 from 3,246,317 ratings. Price: free, with paid Zoom Workplace plans.

10. Overcast

Overcast's 9 October update, version 2026.10, lists 'Interface improvements for iPhone Duo' as one of four changes. A podcast player suits the closed phone well, because most of the time you only need the play controls. But that one line is all Overcast says, so we cannot tell you what changed. Overcast plays ads for other podcasts unless you buy Overcast Premium.

Rating: 4.5 from 47,927 ratings. Price: free with ads, and Overcast Premium removes them.

What happens to apps that are not updated for iPhone Duo?

They run, but they look smaller. Apple says apps built with the iOS 26 SDK or earlier appear in the centre of the open display with empty space around them. Apps built with the iOS 27 SDK fill most of the inner display but avoid the status bar on the right. Only iOS 27.1 SDK builds use the full display.

That is why the dates in the table matter. Apple started accepting iPhone Duo apps on 5 October 2026. A version released before that day, such as Zoom 7.2.1 or Chonky Corgo 2.0.0, came out before Apple accepted iPhone Duo builds, whatever its maker plans next.

Which apps did we leave out, and why?

We left out every app whose support we could not tie to a primary source and a version you can download. Most big names have said nothing yet: on 9 October, the current release notes for Spotify, YouTube, WhatsApp, Gmail, Google Maps, Notion, ChatGPT and Kindle did not mention iPhone Duo. Three more came close:

• Phrase, a meeting-notes app. Version 1.5.0 says 'Phrase now supports iPhone Duo', but it is dated 27 September, before Apple accepted iPhone Duo builds, gives no detail and has 8 ratings.
• Final Cut Camera, from Apple. Its notes say Cinematic mode effects from regular video need an iPhone 18 Pro or an iPhone Duo. That is about the camera hardware, not about the layout.
• Photos and Safari, from Apple. Apple shows Photos beside Mail and two Safari windows side by side, but Split View and second windows are system features, so they say little about either app.

How can you check an app for iPhone Duo support yourself?

Open the app's App Store page and search What's New and the version history for 'iPhone Duo'. Check the version date too, because anything released before 5 October 2026 came out before Apple accepted iPhone Duo builds. On the phone itself, Apple says an optimized app puts its toolbars and tab bars in the column down the side.

Ratings will start to mean more once people have the device. On 9 October 2026 every rating in this table was earned on other iPhones. Run the lookup in the sources again after launch for current numbers.

What else do people ask?

Three questions people ask before they buy an iPhone Duo or install anything on it. The answers come from Apple's own pages and from the App Store, read on 9 October 2026, so check the date at the top of this page before you rely on any of them.

Do all iPhone apps work on iPhone Duo?

Yes, they run, but not all of them fill the screen. Apple says apps built with the iOS 26 SDK or earlier sit in the centre of the open display with empty space around them. Only apps built with the iOS 27.1 SDK or later use the full display.

When can you buy iPhone Duo?

Apple says pre-orders open at 5 a.m. Pacific time on Friday, 16 October 2026, and iPhone Duo goes on sale on Friday, 23 October 2026. Apple's US price starts at $1,999.

Is Chonky Corgo's iPhone Duo version out yet?

Not on 9 October 2026. The App Store version is 2.0.0, which came out before Apple accepted iPhone Duo builds. The two-page layouts, Playtime's fold toys and the hinge treasure chest are in version 2.1, which was in testing on that date.