Code.txt

react-native init RNsplashscreen

Package:
https://github.com/crazycodeboy/react-native-splash-screen

npm i react-native-splash-screen --save
react-native link react-native-splash-screen

Usage:
import SplashScreen from "react-native-splash-screen";
and
  componentDidMount() {
    SplashScreen.hide();
  }

In launch_screen.xml make sure:
android:background="@drawable/screen" for apetools below

Goto:
http://apetools.webprofusion.com/tools/imagegorilla
Upload your 2048x2048 splashscreen and download the zip
Extract and go to Android/res
Copy to app/src/main/res the following directories:
    drawable-ldpi
    drawable-mdpi
    drawable-hdpi
    drawable-xhdpi
    drawable-xxhdpi
    drawable-xxxhdpi

import android.os.Bundle in Main Activity for "onCreate"

Similar is the procedure for Icon which will be focusing on later