React Native makes React one of the most valuable skills you can learn, because about 75% of what you already know from building websites carries straight over to mobile. In this 2025 beginner crash course, I start by breaking down why React Native is the go-to choice today, how it evolved, and why the “React Native apps are slow” take is outdated thanks to the new architecture: JSI (no more old bridge), Turbo Modules (load native modules only when needed), and Fabric (faster UI rendering). Then we jump into the real workflow I use: building with Expo—the recommended way to get started per the official docs. I explain Expo like this: it’s to React Native what Next.js is to React. It simplifies setup, gives you great tooling, supports over-the-air updates, and lets you ship fast without wrestling with Android Studio or Xcode on day one. After fundamentals (View/Text vs div/h tags, Flexbox by default, Touchable components, FlatList vs map, ScrollView, SafeAreaView, Image/ImageBackground, Modal, StatusBar), we build a full-stack mobile movie app. You’ll implement file-based routing, tab navigation, a search screen, movie details, TMDB API fetching with a custom hook, and an Appwrite-backed trending algorithm that tracks real user searches—while keeping the code clean, scalable, and maintainable with TypeScript, responsive design, and NativeWind (Tailwind for React Native).