title: Run react-native on android emulator
body: <p>I try to run react-native app on genymotion android emulator on my mac.
  When I write <code>react-native run-android</code> It gets </p>
  
  <pre><code>Running /usr/local/opt/android-sdk/platform-tools/adb reverse tcp:8081 tcp:8081
  error: closed
  Could not run adb reverse: Command failed: /usr/local/opt/android-sdk/platform-tools/adb reverse tcp:8081 tcp:8081
  Building and installing the app on the device (cd android &amp;&amp; ./gradlew installDebug...
  Could not install the app on the device, read the error above for details.
  Make sure you have an Android emulator running or a device connected and have
  set up your Android development environment:
  https://facebook.github.io/react-native/docs/android-setup.html
  MacBook-Pro-MacBook:ART-CarefulPeople macbook$ 
  </code></pre>
  
  <p>Then I've tried:</p>
  
  <ol>
  <li><code>react-native start</code></li>
  <li><code>react-native run-android</code></li>
  </ol>
  
  <p>The same result.</p>
  
  <p>Then I've tried:</p>
  
  <ol>
  <li><p><code>react-native bundle --entry-file index.android.js --platform android --bundle-output android/app/src/main/assets/index.android.bundle</code></p></li>
  <li><p><code>curl "http://localhost:8081/index.android.bundle?platform=android" -o "android/app/src/main/assets/index.android.bundle"</code></p></li>
  <li><p><code>react-native run-android</code></p></li>
  </ol>
  
  <p>The same result.</p>
  
  <p>I've tried just <code>adb reverse tcp:8081 tcp:8081</code> and it says <code>error: closed</code></p>
  
  <p>When I try to run app on android-sdk emulator it gets the same error above but without <code>error: closed</code>.</p>
  
  <p>From android studio I can run this app and it works on genymotion. 
  Tell me please what should I do to run my app on android emulator?</p>