ReactJS primarily find application in front-end development for web and mobile applications. The ReactJS framework helps us to specifically focus on the visual layer of the app and allows using reusable UI components to flesh out a highly responsive application interface app. The React Native framework, on the other hand, is more centralized towards compiling the native components for app development, across diverse platforms, so that you can use components like ReactJS in the development. So, React JS is more of a subject of React Native.