Change App Name In React Native

For Android

Modify displayName in app.json file

Modify app_name in android/app/src/main/res/values/strings.xml

then Run these commands one by one

cd android
./gradlew clean
cd ..
react-native run-android

For iOS

Modify Display Name in Project target (General Tab)

Select your application project as Host Application in Project target for testing (General Tab)

The generator does not override the strings.xml file located in android/app/src/main/res/values/, so you have to change the app_name variable manually