Generate release mode APK for React-Native project to publish on PlayStore

Good Day All! I hope you are doing Good.

From last couple of days, Me and my friends were doing comparative study of ionic3 and react-native. During that period, we were struggling to generate release mode APK for React-Native project.

Finally, we came across following solution:
 
1.      Create and then copy a keystore file to android/app

keytool -genkey -v -keystore mykeystore.keystore -alias mykeyalias -keyalg RSA -keysize 2048 -validity 10000
 
2.      Setup your gradle variables in android/gradle.properties

MYAPP_RELEASE_STORE_FILE=mykeystore.keystore
MYAPP_RELEASE_KEY_ALIAS=mykeyalias
MYAPP_RELEASE_STORE_PASSWORD=*****
MYAPP_RELEASE_KEY_PASSWORD=*****
 
3.      Add signing config to android/app/build.gradle
 
android {
    signingConfigs {
        release {
            storeFile file(MYAPP_RELEASE_STORE_FILE)
            storePassword MYAPP_RELEASE_STORE_PASSWORD
            keyAlias MYAPP_RELEASE_KEY_ALIAS
            keyPassword MYAPP_RELEASE_KEY_PASSWORD
        }
    }
    buildTypes {
        release {
            signingConfig signingConfigs.release
        }
    }
}

4.      Generate your release APK:
 
cd android && ./gradlew assembleRelease

5.      Your APK will get generated at: android/app/build/outputs/apk/app-release.apk

Special Thanks to Tyler Buchea : http://blog.tylerbuchea.com/react-native-publishing-an-android-app/