Now your activity is ready to run some JavaScript code.
You have now done all the basic steps to integrate React Native with your current application. Now we will start the React Native packager to build the index.bundle package and the server running on localhost to serve it.
To run your app, you need to first start the development server. To do this, simply run the following command in the root directory of your React Native project:
Now build and run your Android app as normal.
Once you reach your React-powered activity inside the app, it should load the JavaScript code from the development server and display:

You can use Android Studio to create your release builds too! It’s as easy as creating release builds of your previously-existing native Android app. There’s just one additional step, which you’ll have to do before every release build. You need to execute the following to create a React Native bundle, which will be included with your native Android app:
Don’t forget to replace the paths with correct ones and create the assets folder if it doesn’t exist.
Now just create a release build of your native app from within Android Studio as usual and you should be good to go!
At this point you can continue developing your app as usual. Refer to our debugging and deployment docs to learn more about working with React Native.