App.js

import React, { Component } from 'react';
import {
  SafeAreaView,
  StyleSheet,
  ScrollView,
  View,
  Text,
  StatusBar,
  Button,
  TextInput,
} from 'react-native';
import { createSwitchNavigator, createAppContainer } from 'react-navigation';
import { createStackNavigator } from 'react-navigation-stack';

import LogoScreen from './src/screens/LogoScreen';
import LoginScreen from './src/screens/LoginScreen';
import SignUpScreen from './src/screens/SignUpScreen';
import ForgotPasswordScreen from './src/screens/ForgotPasswordScreen';
import HomeScreen from './src/screens/HomeScreen';

// Create navigation objects
const AuthStack = createStackNavigator({
  SignUp: {
    screen: SignUpScreen,
    navigationOptions: {
      header: null,
    },
  },
  Login: {
    screen: LoginScreen,
    navigationOptions: {
      header: null,
    },
  },
  Forgot: {
    screen: ForgotPasswordScreen,
    navigationOptions: {
      header: null,
    },
  },
});
const AppStack = createStackNavigator({
  Home: {
    screen: HomeScreen,
    navigationOptions: {
      header: null,
    },
  },
});
const AppNavigator = createSwitchNavigator({
  Logo: LogoScreen, // check if user is authenticated
  Auth: AuthStack, // if not authenticated
  App: AppStack, // if authenticated
});
const AppContainer = createAppContainer(AppNavigator);

class App extends React.Component {
  render() {
    return <AppContainer />;
  }
}

export default App;