React Native is a JavaScript framework for building native mobile apps. It’s based on React, Facebook’s JavaScript library for building user interfaces, but instead of targeting the browser, it targets mobile platforms. In other words: web developers can now write mobile apps that look and feel truly native without having to learn a new language or syntax.
React Native lets you build your app faster. Instead of recompiling, you can reload your app instantly. With hot reloading, you can even run new code while retaining your app state. And because React Native uses the same fundamental UI building blocks as regular iOS and Android apps, you can just drop existing Objective-C or Java code into your React Native app without any rewriting required.
Plus, because most of the code you write can be shared between platforms, React Native makes it easy to simultaneously develop for both Android and iOS—without having to build two separate apps.
In short, React Native is a powerful tool that lets web developers use their existing skillset to build native mobile apps quickly and easily.