Incorrect Orientations on iPhone Duo

[zbarbuto]

Before submitting a new issue

• I tested using the latest version of the library, as the bug might be already fixed.
• I tested using a supported version of react native.
• I checked for possible duplicate issues, with possible answers.

Bug summary

I'm not 100% sure if this is a bug or expected behaviour, but in testing on an iPhone Duo using Xcode 27 I noticed the following:

1. The orientation is not updated when unfolding the device, the orientation is not updated
2. The orientations that are reported when rotating an unfolded Duo are not as you would expect

Consider the minimal app in the "Steps to Reproduce" below. A folded iPhone Duo reports portrait for both interface and device orientation which is what we would expect.

However, when we unfold these remain unchanged - the now landscape device is still considered portrait:

As we continue to rotate the unfolded device, the device orientations are the opposite of what we'd expect - with portrait reporting as landscape in the device orientation, while the interface orientation always reports portrait.

No matter how we rotate the device, the interface orientation is always considered portrait and the device is considered landscape for portrait and portrait for landscape. The folded device on the other hand reports as you would expect:

Screen.Recording.2026-09-24.at.1.51.25.pm.mov

Library version

3.0.2

Environment info

System:
  OS: macOS 27.0
  CPU: (12) arm64 Apple M2 Max
  Memory: 452.44 MB / 64.00 GB
  Shell:
    version: "5.9"
    path: /bin/zsh
Binaries:
  Node:
    version: 24.3.0
    path: ~/.nvm/versions/node/v24.3.0/bin/node
  Yarn:
    version: 1.22.22
    path: ~/.nvm/versions/node/v24.3.0/bin/yarn
  npm:
    version: 11.15.0
    path: ~/.nvm/versions/node/v24.3.0/bin/npm
  Watchman: Not Found
Managers:
  CocoaPods:
    version: 1.16.2
    path: ~/.rbenv/shims/pod
SDKs:
  iOS SDK:
    Platforms:
      - DriverKit 27.0
      - iOS 27.1
      - macOS 27.0
      - tvOS 27.0
      - visionOS 27.0
      - watchOS 27.0
  Android SDK:
    API Levels:
      - "29"
      - "31"
      - "33"
      - "34"
      - "35"
      - "36"
    Build Tools:
      - 29.0.3
      - 30.0.2
      - 30.0.3
      - 31.0.0
      - 33.0.0
      - 33.0.1
      - 34.0.0
      - 35.0.0
      - 36.0.0
      - 36.1.0
    System Images:
      - android-28 | Google ARM64-V8a Play ARM 64 v8a
      - android-29 | Google Play ARM 64 v8a
      - android-34 | Google APIs ARM 64 v8a
      - android-34 | Google Play ARM 64 v8a
      - android-35 | Google Play Tablet ARM 64 v8a
      - android-36 | Google Play ARM 64 v8a
      - android-37.0 | Pre-Release 16 KB Page Size Google Play ARM 64 v8a
      - android-37.1 | 16 KB Page Size Google Play ARM 64 v8a
    Android NDK: Not Found
IDEs:
  Android Studio: 2025.3 AI-253.31033.145.2533.15113396
  Xcode:
    version: 27.1/27A9269
    path: /usr/bin/xcodebuild
Languages:
  Java:
    version: 17.0.14
    path: ~/.jenv/shims/javac
  Ruby:
    version: 2.7.2
    path: ~/.rbenv/shims/ruby
npmPackages:
  "@react-native-community/cli":
    installed: 20.1.0
    wanted: 20.1.0
  react:
    installed: 19.2.3
    wanted: 19.2.3
  react-native:
    installed: 0.86.0
    wanted: 0.86.0
  react-native-macos: Not Found
npmGlobalPackages:
  "*react-native*": Not Found
Android:
  hermesEnabled: true
  newArchEnabled: true
iOS:
  hermesEnabled: true
  newArchEnabled: true

Steps to reproduce

  const interfaceOrientation = useInterfaceOrientation();
  const deviceOrientation = useDeviceOrientation();
  const interfaceLabel = Object.keys(Orientation).find(
    key =>
      Orientation[key as keyof typeof Orientation] === interfaceOrientation,
  );
  const deviceLabel = Object.keys(Orientation).find(
    key => Orientation[key as keyof typeof Orientation] === deviceOrientation,
  );

  return (
    <View style={styles.container}>
      <Text>
        Interface Orientation: {interfaceOrientation} ({interfaceLabel})
      </Text>
      <Text>
        Device Orientation: {deviceOrientation} ({deviceLabel})
      </Text>
    </View>
  );

React Native does not fully support Xcode 27 yet but can be run by using a diff similar to below:

https://github.com/lodev09/react-native-true-sheet/pull/843/changes#diff-dc87f0be9c8ca3a727efb4fd5d77e6b551d8cee9fe22fea2c07062f907f6507bR15

Reproducible example repository

No response

[gladiuscode]

Hi @zbarbuto

I've spent a bit reading the documentation and through the help of Claude I've managed to find a way to adjust the code so that on iOS it is able to properly update the interface and device orientation to acceptable values, both. It is a primitive, unrefined change tho.

That said, I don't plan on merging this soon since even React Native itself is catching on the latest changes from Apple and I want to dive deeper on the code changes themself to be sure that I'm actually delivering something worth of quality, although you can test it yourself by checking out the PR branch.

I would really appreciate a feedback and double check using your simulator, so do let me know if you find the time to do so.

[zbarbuto]

Hi @gladiuscode. Thanks for looking into this so quickly.

I had a poke around with the branch on iPhone Duo.

Interestingly, unfolding from portrait is reporting inverted landscape orientations - i.e. interface is landscapeLeft, device is landscapeRight

The cause is likely the new function convertToDisplayRelativeFrom which does this mapping of one device orientation to another:

switch deviceOrientation {
        case .portrait:
            return .landscapeRight
        case .landscapeRight:
            return .portraitUpsideDown
        case .portraitUpsideDown:
            return .landscapeLeft
        case .landscapeLeft:
            return .portrait
        default:
            return deviceOrientation
 }

Interestingly, when you unfold the device and breakpoint in onSceneGeometryChanged and check UIDevice.current.orientation, Apple does seem to still report the orientation as portrait

In fact, if you just run a vanilla swift app that does nothing but print UIDevice.curent.orientation on an unfolded duo you get portrait:

Similarly, rotating gives you "landscape"

I can't find any docs from Apple on why this would be the case - perhaps to them "Portrait" just means the "natural way to hold the device" which, for a duo that you just unfolded, would be what looks like "landscape", since you haven't technically "rotated" the device in the process of unfolding. Just a guess. Or maybe it's because the folded screen does still exist as a screen and is still technically portrait.

Therefore, I'm actually not sure that the mapping one orientation to the other is the right approach here. Feels a bit like it's lying to React Native about what the OS considers the orientation. Although it's sort of a philosophical question for the library itself: do you want to report the orientation the OS reports as-is it or do you want to base it on width vs height values? For the latter, you can sort of already rely on window dimensions from React Native itself. What's more important out of orientation-director in my opinion is that "something changed" - i.e. the device was rotated or unfolded.

IMO, this library should just report whatever Apple does. So if a regular native app has UIDeviceOrientation of .portrait and UIInterfaceOrientation of landscapeLeft then this should probably match. As long as those values correctly update after folding/unfolding.

For comparison, native app readings of UIDeviceOrientation and UIInterfaceOrientation for folded and after unfolding on a duo simulator:

And as split screen:

After looking into this, a better title for this issue might be "Orientations do not update on unfold of Duo".

[gladiuscode]

Hi @zbarbuto

thank you for spending time to look into this.

I agree, there is a choice to make here and it depends on what we want the library to notify all devs about Duo, although there is already a "not so intuitive" behavior from Apple itself, related to the interface vs device orientation that kind of confused me since the earlier version of the library, based on: UiInterfaceOrientation.

I like your way tho, I think too that we should compare what a native app does with the primitive APIs and let the library expose the same, I don't want the library to be a wrapper that changes the behavior that the devs may rely on.
On the other hand tho, I'd like the library to be consistent between the two operating system, starting from the code architecture that you can look into, I think it benefits to have the same behavior on both platforms imo, where possible of course.

I wish Apple simply gave us a proper guide to interpret the various values, perhaps the "interpret" phase should be delegated to each app case, i dunno at this point.

I'll review the code properly this upcoming week while also waiting for .88 to align the library to.

I'll update the issue as well.

Thanks!