Infinite Red

Expo is a React Native development and deployment platform for building native iOS, Android, and web apps from a shared codebase. Its CLI and development tools support local development, device and simulator testing, web support, app-store builds and submissions, and automated workflows for builds, tests, releases, and over-the-air updates. The platform also provides cloud simulators, production performance monitoring, hosting, and APIs for native app capabilities.

React Native is an open-source framework for building native applications with React. JavaScript components, declarative UI, hooks, and Suspense are rendered through native platform UI on Android, iOS, and other platforms, while Fast Refresh applies JavaScript changes without rebuilding the native app. Native Modules allow JavaScript code to call platform code directly, and the framework can be adopted incrementally in existing applications or used with production frameworks such as Expo. React Native is developed by companies and individual core contributors and is distributed under the MIT license.

Mobile Dev is a Codex plugin for developing and debugging Android and iOS applications alongside a Codex desktop chat. It supports Expo, React Native, SwiftUI, and other native mobile projects, and can stream iOS simulators, Android emulators, and connected devices into a device panel. The plugin provides device selection and booting, taps, drags, text input, accessibility inspection, screen or element annotations, and MCP-based app control. It combines iOS unified logs, Android logcat, and Metro messages; logs can be searched, filtered, scoped to the foreground app, and sent to chat with an error stack trace. Its performance tools record CPU and memory activity, thread charts, display FPS, Android frame-pacing and jank statistics, and selected interaction ranges for comparison and analysis in Codex. The prebuilt distribution targets Codex desktop on Apple Silicon Macs and includes bundled runtimes. It is installed through Codex's plugin marketplace and requires the relevant Xcode, Android SDK, simulator, emulator, or device tooling. The repository is maintained by Callstack's incubator organization.

React is a JavaScript library for building web and native user interfaces. It uses declarative views that update the appropriate components when application data changes, and lets developers compose encapsulated, state-managing components into larger interfaces. React code can use JSX, an HTML-like syntax for defining interface elements, although JSX is optional. The library is designed for gradual adoption, can render on the server with Node, and supports mobile applications through React Native. Its core repository is developed openly on GitHub under the MIT license.

Quickdraw is an MIT-licensed, open-source infinite-canvas whiteboard SDK for React, React Native/Expo, and plain JavaScript applications. It provides freehand pressure ink, highlighters, shapes, arrows, lines, text, sticky notes, images, selection and transformation tools, laser presentation pointers, themes, grids, palm rejection, and PNG export. Its data model emits JSON-safe diffs for real-time synchronization over an application-chosen transport, with support for persistence, undo/redo, and stroke-by-stroke replay. The project provides separate core, React, and React Native packages; the core is plain ESM with zero runtime dependencies and can run in modern browsers without a build step. The repository states that it is free for commercial use and has no license fee.