Mark from Expo demonstrates VisionCamera frame processors for tasks such as face recognition, object detection, and QR scanning. He explains how JSI host functions and host objects enable synchronous access between JavaScript and native code without copying large camera frames through the bridge.
React Native EU 2021 - Virtual Conference: Day I
Callstack host Luca introduces React Native EU 2021, a virtual conference featuring React Native developers from Expo, Facebook, Microsoft, Callstack, and other teams sharing technical talks and production experience.
Josh Gross describes migrating more than 1,000 Facebook app surfaces to Fabric through gradual, per-surface rollouts. The work took about two years to enable the first surface and nine more months to cover the rest. He shares issues involving undocumented behavior, device-specific crashes, and screens that depended on event ordering.
Calif from Microsoft covers platform updates, Hermes support, developer tools, and UI frameworks for desktop React Native. Examples include CodePush for Windows, Fluent UI React Native, and XAML controls exposed to JavaScript. He also shows apps from Office, Xbox, a digital classroom, and Mashreq Bank.
The later sessions cover Unity integration for games, React Navigation 6, native code for background audio and timers, and accessible cross-platform components with React Native Aria. Other speakers discuss moving from web React to mobile, faster iteration with Expo, on-device machine learning with MediaPipe and TensorFlow Lite, GraphQL data fetching with React Query, and local notifications with Notifee.
Takeaways
- Use JSI frame processors when camera workloads need direct, high-frequency access to native image data.
- Roll out renderer changes gradually and instrument surfaces, since undocumented assumptions and event ordering can cause production issues.
- Test desktop targets and real devices early; platform parity and simulator behavior do not guarantee identical results.
- Move recurring background work to native code when frequent bridge events create complexity or timing problems.
- Choose libraries and architecture around the app’s needs, including navigation performance, accessibility, offline data, and update workflows.
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What was claimed 9
- built
“I’ve been working ... primarily on React Native for Windows.”
1:16inWhat’s next for React Native for Desktop?YouTube Verified5 sources· Talk
- useshundreds of apps in the Microsoft Store use it
“The Settings team is using React Native”
4:23inReact Native at Scale: How Microsoft is betting big on React Native to target BILLIONS of usersYouTube Verified6 sources· Talk
- uses
“MediaPipe internally uses TensorFlow Lite”
11:04inMachine Learning with React Native using MediaPipe and TFLiteYouTube Verified2 sources· Talk
- uses
“React Native Aria is used with many NativeBase components to make them accessible”
26:46inBuilding Accessibility Hooks for React Native & WebYouTube Verified2 sources· Talk
- feature
Meta: The Facebook app was completely powered by the new architecture as of the previous month.The Facebook app was completely powered by the new architecture as of the previous month.“React Native in the Facebook app is now completely powered by the new architecture.”
YouTube Unverified1 source· Talk
- featureReact Native for Windows: Experimental binary distribution reduced build time by about 80% and disk usage by about half in tests.
“build time was about 80% faster, and disk usage was about half”
YouTube Unverified1 source· Talk
- featureReact Native Aria: Provides hooks for accessible UI primitives across React Native and web.
“a set of React hooks to build accessible UI primitives for React Native and web”
YouTube Unverified1 source· Talk
- featureExpo: Provides tools and services to build, submit, and update React Native apps.
“Expo provides a component SDK, tools like Expo Go, and services to build, submit, and update your app.”
YouTube Unverified1 source· Talk
