Video: Expo vs React Native: Streamlined Development

React Native is a framework that allows developers to build cross-platform mobile applications using React and JavaScript. It enables the same codebase to render on both iOS and Android platforms by using native views instead of web views.

The core differences are that React Native uses proper native views instead of drawing views to Skia like in Chrome. This allows for platform optimizations such as smooth scrolling, gestures, and complex animations. React Native also supports the use of multiple threads and custom native clients for extra functionality.

Some challenges include the need to create a native runtime to get started, managing dependencies which are harder than in web development, distributing the app via App Store or Google Play Store which involves complex code signing, and frequent and complex upgrades requiring familiarity with iOS and Android native development.

Expo simplifies React Native development by providing tools such as a reusable pre-built runtime, fast iteration speed, and integrated cloud services. It allows developers to create and run apps without native builds, manage dependencies easily, publish apps with a single command, and add native code or customize the client with minimal complexity.

Expo CLI is a modern Node.js Command Line Interface that helps developers interface with the bundler, start a development server, and perform various development tasks. Developers can install Expo CLI globally and create new projects with commands like 'expo init' and run them on iOS, Android, or web platforms using NPM scripts.

Expo Go allows developers to instantly open their app on iOS and Android without needing to make native builds. It includes most of the APIs needed for complex native apps built ahead of time, reducing the complexity and time required to launch a 'Hello World' app, making it as easy as web development.

Expo uses a tool called Expo Application Services (EAS) for deploying apps. EAS automates native code signing, validation, and submission to the App Store or Google Play Store. Developers can submit their app with a single command, simplifying the traditionally difficult and error-prone process of deploying mobile apps.

Over-the-air updates in Expo allow developers to update JavaScript and assets in their app instantly. By running 'expo publish,' the JS bundle is pushed to a hosting service, which the app's runtime checks for updates. The next time the user opens the app, the updated version is downloaded in the background and presented.

Expo has two main workflows: the Managed Workflow and the Bare Workflow. The Managed Workflow allows developers to avoid working directly with native code and maximizes cross-platform configuration. The Bare Workflow provides full control over every aspect of the project, requiring manual updates for native configurations.

The Expo SDK is a set of npm packages versioned together to ensure compatibility. It includes core primitives and community packages that support iOS, Android, and web platforms. The SDK simplifies dependency management and provides a reliable versioning system to solve common issues encountered in React Native development.