title: react-native error - Check the render method of `App`
body: <p>I was running my react-native expo managed project by <code>expo start</code> command and I don't know that what is wrong in my code that I got this error -</p>
  <pre><code>Error: Element type is invalid: expected a string (for built-in components) or a class/function (for composite components) but got: undefined. You likely forgot to export your component from the file it's defined in, or you might have mixed up default and named imports.
  
  Check the render method of `App`.
  
  This error is located at:
      in App (created by ExpoRoot)
      in ExpoRoot (at renderApplication.js:45)
      in RCTView (at View.js:34)
      in View (at AppContainer.js:106)
      in RCTView (at View.js:34)
      in View (at AppContainer.js:132)
      in AppContainer (at renderApplication.js:39)
  </code></pre>
  <p>This is my code -</p>
  <pre><code>export default function App() {
    let [fontsLoaded] = useFonts({
      'PoetsenOne-Regular': require('./assets/fonts/PoetsenOne-Regular.ttf'),
    });
  
    if (!fontsLoaded) {
      return &lt;AppLoading /&gt;;
    } else{
      return (
        &lt;View style={styles.container}&gt;
          &lt;Text style={styles.container}&gt;Open up App.js to start working on your app!&lt;/Text&gt;
          &lt;StatusBar style=&quot;auto&quot; /&gt;
        &lt;/View&gt;
      );
    }
  }
  </code></pre>
  <p>This is my stylesheet -</p>
  <pre><code>const styles = StyleSheet.create({
    container: {
      flex: 1,
      backgroundColor: '#fff',
      alignItems: 'center',
      justifyContent: 'center',
      fontFamily: &quot;PoetsenOne-Regular&quot;
    },
  });
  </code></pre>