Go to App folder (for example Calculator) npm install // to install dependences react-native start

A. running on Android Open a new command prompt and run react-native run-android inside the same folder to launch the app on your Android emulator. react-native run-android https://facebook.github.io/react-native/docs/getting-started.html

B. Running on IOS Open a new command prompt and run react-native run-android inside the same folder to launch the app on your Android emulator. react-native run-ios https://facebook.github.io/react-native/docs/getting-started.html

C. Running on Windows Desktop Open a new command prompt and run react-native run-android inside the same folder to launch the app on your Android emulator. react-native run-windows https://www.microsoft.com/developerblog/real-life-code/2016/05/27/Creating-Universal-Windows-Apps-with-React-Native.html