The two sizes
Each display has exactly one accepted size, in portrait or landscape:
| Slot | Portrait | Landscape | Status |
|---|---|---|---|
| iPhone Duo (outer display) | 1398 × 2034 | 2034 × 1398 | Optional |
| iPhone Duo (inner display) | 2007 × 2853 | 2853 × 2007 | Optional |
The rest of the App Store rules still apply: PNG or JPEG, no alpha channel or transparency, and up to 10 screenshots per slot.
When they become required
Optional today. Required from April 2027 for apps built with the iOS 27.1 SDK or later. Uploading Duo screenshots adds an 'optimized for iPhone Duo' badge.
So the deadline depends on your build, not just the calendar. If you ship a build made with the iOS 27.1 SDK or later after April 2027, plan to have both Duo sets ready. Until then, uploading them is your choice, and doing so adds the "optimized for iPhone Duo" badge.
Unlike the smaller iPhone slots, the Duo slots don't list a fallback size. App Store Connect won't scale your regular iPhone screenshots into them, so skipping them means there is no Duo set on your page.
How the shapes differ
The two displays are very different shapes, and neither matches a regular iPhone. Comparing the long side to the short side:
- Main iPhone slot (1179 × 2556): about 2.17 to 1
- Duo outer display (1398 × 2034): about 1.45 to 1
- Duo inner display (2007 × 2853): about 1.42 to 1
Both Duo displays are much less tall than a regular iPhone, and the inner one is larger in pixels too. That means you can't just resize your existing iPhone screenshots. The layout needs to change: less vertical room for a headline above the device, more horizontal room to use.
Capturing the screens
You need app screens at both Duo layouts. If your app already adapts to different widths (the way it would for iPad split view), most of the work is done. Capture each display on an iPhone Duo device or simulator, using the screens you planned and with the same sample data you used for your main iPhone set so the story stays consistent.
The inner display is the one to look at closely. If your app shows more there, such as a list and a detail view side by side, or extra controls, that is worth showing off, because it is what makes the Duo version different.
Planning one story for both displays
You don't need two different stories. Use the same order of screens you use for your regular iPhone set, the promise, the main proof and the reason to pick yours, as covered in what to put on your first three screenshots. Then adapt each one:
- Outer display: close to your regular iPhone design, with a shorter headline and a slightly smaller device frame to fit the shorter canvas.
- Inner display: treat it more like a small iPad layout. Put the headline beside the device or above a wider frame, and let the inner screen's extra space show.
- Keep colours, fonts and key words the same as your main iPhone set, so the listing feels like one product.
- If a feature only makes sense on the inner display, give it its own screenshot in the inner set.
App previews for Duo
If you use app preview videos, iPhone Duo has its own preview slot: 886 × 1920 portrait or 1920 × 886 landscape.
Designing them in Phonepose
Phonepose has 3D models for both the iPhone Duo outer and inner displays, and Duo screenshots have their own tab in the editor, separate from your regular iPhone screens. You switch the size at the top to see each layout, and downloads come out at 1398 × 2034 and 2007 × 2853. You can see the models on the mockups page and start from any of the templates.
Common questions
Can I upload only one of the two Duo sizes?
The two slots are paired, one for each display. Since the badge and the April 2027 requirement are about supporting the device, plan to fill both rather than picking one.
Do I still need my regular iPhone screenshots?
Yes. Duo screenshots are added alongside your regular iPhone set, not instead of it. iPhone with Dynamic Island, medium (6.1" / 6.3") is still required for every iPhone app, at 1179 × 2556, 1206 × 2622 portrait.
Should Duo screenshots be portrait or landscape?
Both are accepted for each display. Pick the orientation that matches how people use your app on that display, and keep it the same across the set so the screenshots line up when people swipe.
Will my existing screenshots be rejected if I skip Duo for now?
No. Today the Duo slots are optional. Optional today. Required from April 2027 for apps built with the iOS 27.1 SDK or later.
Checklist
- Capture screens for the outer display and inner display.
- Reuse the story from your main iPhone set, adapted to each shape.
- Export the outer set at 1398 × 2034, 2034 × 1398 and the inner set at 2007 × 2853, 2853 × 2007.
- Check them with the screenshot validator.
- Upload both in App Store Connect before your first iOS 27.1 SDK build after April 2027.
For every other size, see App Store screenshot sizes in 2026. For the design process from capture to upload, read how to make App Store screenshots.