React Native for Apple Vision Pro and visionOS

The guests distinguish VR as a fully immersive virtual world, AR as digital elements overlaid on the real world, and XR or mixed reality as covering both. They describe Apple Vision Pro as blending digital content with a camera view of the surroundings, controlled through eyes, hands, and voice. Its visionOS supports windows, 3D volumes, and shared or immersive spaces.

Callstack’s visionOS project is an out-of-tree React Native platform, with changes to core code that allow it to compile for visionOS. The team says the work involved substantial research across React Native and its libraries, despite roughly 1,000 to 2,000 lines of code changes. They see possible uses in porting existing multi-platform apps and building immersive data visualizations or streaming experiences.

The initial release supports greenfield apps, both React Native architectures, Hermes, and a CLI init command. The guests describe it as experimental, with third-party library support still developing; Reanimated compiled in a local hack but was not officially supported. Brownfield apps can add SwiftUI for native visionOS features, while running immersive spaces and volumetric windows from JavaScript remained a future idea.

The team added visionOS support across CocoaPods dependencies and addressed unsupported APIs, including UIScreen, which does not fit a window-based device. They kept visionOS aligned with iOS for platform checks so apps can reuse much of the iOS ecosystem, and built a custom Metro file resolver. Work on Hermes simulator builds also produced a fix that enabled local builds for macOS.

Callstack’s next steps included production readiness, CI, end-to-end testing, and tools for debugging, profiling, and testing. The longer-term idea was to connect React Native with WebXR through JSI, potentially extending it to other headsets. The team invited feedback and contributions to its public repository.