It's safe to say that your React Native apps will probably be written mostly in JavaScript. There may be some native modules and custom UI components, but for the most part, all of the views and business logic will likely be written in JSX and JavaScript. And if you're using modern JavaScript development techniques, you'll also be using language constructs introduced with ES6, ES7, and beyond. These may be available natively as part of the JavaScript interpreter bundled with React Native (JavaScriptCore) or polyfilled by the Babel transpiler. Since JavaScript probably constitutes the majority of any given React Native app, this should be the first part we optimize in order to squeeze extra performance out of the app.
This recipe will provide some helpful tips for optimizing JavaScript code to make it as performant as possible.
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