iPhone Duo App Store Connect checklist: screenshots, sizes, and submission
You cannot upload iPhone Duo screenshots to App Store Connect yet. Here is what is confirmed about sizes and requirements for when the feature ships.
What is already confirmed about sizes
Even though you cannot upload them yet, the required dimensions for the eventual screenshot upload have already been published:
- Outer display: 1398 x 2034 pixels in portrait, or 2034 x 1398 pixels in landscape
- Inner display: 2007 x 2853 pixels in portrait, or 2853 x 2007 pixels in landscape
Accepted file formats are JPEG, JPG, or PNG, and files must not contain transparency.
These screenshots are optional
Worth noting explicitly: Apple has said these iPhone Duo-specific screenshots are optional, not required, for App Store submissions. Whether your specific app's listing calls for them will be visible in the Media Manager section of App Store Connect once the upload feature ships.
What to prepare now
Even without the ability to upload yet, there is real prep work worth doing ahead of time:
- Get your app's layout genuinely working across the outer display, the inner display, and Split View, using ArrangementView and reserved regions rather than device-specific branching — see our adaptive layouts guide for the details
- Capture your own reference screenshots at the confirmed dimensions using the Simulator, so you are not scrambling once the upload feature ships
- Review your app's marketing copy and App Store description for any device-specific claims that assume a single-screen phone, since iPhone Duo owners are a growing part of your potential audience
Why this matters for discoverability
Once Apple does enable an "optimized for iPhone Duo" style badge or listing treatment — which has not been formally detailed yet, but tracks with how Apple has handled similar hardware-specific badges in the past, such as Apple Watch or iPad optimization labels — apps that already have their layout, camera, and Split View behavior correct will be in a much better position to adopt it immediately rather than scrambling after the fact.
For the rest of the toolchain you will need to be testing against ahead of that submission window, see our guide to iOS 27, Xcode 27.1 beta, and macOS Tahoe 26.6.
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Spotted something to fix, or an app we should cover?
This article is independent research, cross-checked against Apple's developer documentation. If something's out of date, or you know an app that deserves a look, let us know — and if you're building for iPhone Duo yourself, we're happy to talk.
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