title: Change loading icon size for different DPI deivces
body: <p>I am working on application which is implemented using Expo and react native. I have splash screen in my app.The icon in splash screen loading screen is coming correct in android devices but very small in IOS devices ( in different dpi).I want to make icon resize based on dpi which present  under loading .Can anyone help me out here.Thank you.</p>
  
  <p>Config file:-</p>
  
  <pre><code> "expo": {
      "name": "ExpoApp",
      "description": "No description",
      "slug": "evosus",
      "privacy": "unlisted", // public
      "sdkVersion": "19.0.0",
      "version": "1.0.0",
      "orientation": "portrait,landscape",
      "primaryColor": "green",
      "icon": "./assets/icons/ball.png",
      //"icon": "./assets/icons/logo_Dark.png",
      "notification": {
        "icon": "./assets/icons/ball.png",
        "color": "#000000"
      },
      "loading": {
        //"icon": "./assets/icons/loading-icon.png",
        "icon": "./assets/icons/icon.png",//I want to resize this icon based on screen dpi
        "hideExponentText": true
      },
      "packagerOpts": {
        "assetExts": [
          "ttf"
        ]
      },
      "ios": {
        "supportsTablet": true
      }
      //,"androidStatusBarColor": "#444444"
    }
  }
  </code></pre>
  
  <p>App.js component:-</p>
  
  <pre><code>import React from 'react';
  import { Platform, StatusBar, StyleSheet, View } from 'react-native';
  import { AppLoading, Asset, Font, SQLite } from 'expo';
  import { Ionicons, EvilIcons } from '@expo/vector-icons';
  import RootNavigation from './navigation/RootNavigation';
  
  // Services
  import DB from "./src/Services/DBDefinitionService";
  import appService from "./src/Services/AppService";
  
  console.ignoredYellowBox = [ 'Setting a timer' ];
  
  export default class App extends React.Component {
    state = {
      assetsAreLoaded: false,
    };
  
    componentWillMount() {
      this._loadAssetsAsync();
      // Added by Anil G on 23/08/2017
      this.db_init();
      this.db_device_info_save();
    }
  
    render() {
      if (!this.state.assetsAreLoaded &amp;&amp; !this.props.skipLoadingScreen) {
        return &lt;AppLoading/&gt;;
      } else {
        return (
          &lt;View style={styles.container}&gt;
            {Platform.OS === 'ios' &amp;&amp; &lt;StatusBar barStyle="default" /&gt;}
            {Platform.OS === 'android' &amp;&amp;
              &lt;View style={styles.statusBarUnderlay} /&gt;}
            &lt;RootNavigation /&gt;
          &lt;/View&gt;
        );
      }
    }
  
    async _loadAssetsAsync() {
      try {
        await Promise.all([
          Asset.loadAsync([
            require('./assets/images/robot-dev.png'),
            require('./assets/images/robot-prod.png'),
          ]),
          Font.loadAsync([
            // This is the font that we are using for our tab bar
            Ionicons.font,
            EvilIcons.font,
            // We include SpaceMono because we use it in HomeScreen.js. Feel free
            // to remove this if you are not using it in your app
            { 'space-mono': require('./assets/fonts/SpaceMono-Regular.ttf'),
              'roboto-regular': require('./assets/fonts/Roboto-Regular.ttf'),
              'roboto-medium': require('./assets/fonts/Roboto-Medium.ttf'),
           },
          ]),
        ]);
      } catch (e) {
        // In this case, you might want to report the error to your error
        // reporting service, for example Sentry
        console.warn(
          'There was an error caching assets (see: App.js), perhaps due to a ' +
            'network timeout, so we skipped caching. Reload the app to try again.'
        );
        console.log(e);
      } finally {
        this.setState({ assetsAreLoaded: true });
      }
    }
  
      async db_init() {
          await DB.init();
      }
  
      async db_device_info_save() {
          await appService.device_info_save();
      }
  
  }
  
  const styles = StyleSheet.create({
    container: {
      flex: 1,
      backgroundColor: '#fff',
    },
    statusBarUnderlay: {
      height: 24,
      backgroundColor: 'rgba(0,0,0,0.2)',
    },
  });
  </code></pre>