Summary

In this chapter, we introduced the main concepts of the JavaScript library React. We have shown that React is declarative, component-based, and follows a learn once, write everywhere approach. These concepts are the base for the cross-platform mobile development framework React Native.

You saw the main advantages of this framework, namely the huge community that provides additional packages and libraries, the fact that a lot of operating systems besides iOS and Android are available, and the usage of native elements via the Bridge or JSI. Last but not least, you discovered Expo as one way of setting up a React Native app, and you know when to use which Expo workflow.

In the next chapter, we will briefly talk about the most important facts and features of JavaScript and TypeScript.