The simplest way of debugging code is to use Chrome. You don’t need to install any other apps. on Android emulator, or shake real devices, you will see the in-app developer menu. Tap “Debug JS Remotely”. The Chrome debugger will be opened automatically. You still need to open Developer Tools in Chrome manually. Open source files in the Sources tab, you can set breakpoints here. (Update on Feb 26, 2018: due to a bug in React Native Android, if the app says it failed to connect the debugger and the URL in Chrome is not
http://localhost:8081/debugger-ui/, change the URL to
http://localhost:8081/debugger-ui/, kill the app, and try again.)
All credit gose to this website : https://codeburst.io/react-native-debugging-tools-3a24e4e40e4


http://localhost:8081/in web browser ?