title: Expo/GenyMotion throws "ADB server didn't ACK" when running project
body: <p>I'm trying to set up a React Native project using GenyMotion and Expo on Ubuntu. However, when I click the 'Device' button in Expo to package the app onto the emulator, I get the following error in the Expo console:</p>
  
  <p><a href="https://i.stack.imgur.com/JbecU.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/JbecU.png" alt="ADB Server didn&#39;t ACK error"></a></p>
  
  <p>I initially tried to use React Native through Android Studio, with the inbuilt Android emulator, so I thought the issue might that my computer hasmultiple ADB versions (when I ran <code>$ adb --start-server</code> from the terminal, it'd run the Android Studio binary, not the GenyMotion one). So I:</p>
  
  <ul>
  <li>Removed everything Android Studio related that I could find, including the SDK at <code>Android/Sdk/</code> and now <code>$ adb --start-server</code> </li>
  <li>Ran <code>$ sudo apt-get remove adb android-tools-adb</code></li>
  <li><p>Set the filepath for the Android SDK in GenyMotion to my GenyMotion Android SDK. But I'm guessing is the same as the default setting, so I don't know if I needed to do this?</p>
  
  <p><a href="https://i.stack.imgur.com/PuvSD.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/PuvSD.png" alt="GenyMotion Android SDK"></a></p></li>
  <li><p>Removed all path variables related to Android Studio from my <code>.bashrc</code> file, including <code>$ANDROID_HOME</code>. (should I instead set <code>$ANDROID_HOME</code> to point to the GenyMotion Android SDK?</p></li>
  </ul>
  
  <p>After doing the above, <code>$ ps -aux | grep 5037</code> outputs the following:</p>
  
  <p><a href="https://i.stack.imgur.com/JDcTz.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/JDcTz.png" alt="ps output"></a></p>
  
  <p>even after quitting GenyMotion and Expo, so it looks like there is still a forked ADB daemon running. If I <code>cd</code> to my GenyMotion SDK and run <code>$ ./adb kill-server</code> (after quitting GM and Expo) that process doesn't show up in the output of <code>ps</code> anymore. However, interestingly, if I run <code>$ ./adb start-server</code> I get this: </p>
  
  <p><a href="https://i.stack.imgur.com/DUI4g.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/DUI4g.png" alt="ADB out of date"></a></p>
  
  <p>But I don't know how to udpate the GenyMotion version of ADB. This also seems to indicate there are different ADB server and client programs. Is this correct? I have only ever interacted with the <code>adb</code> binary in the SDK folders.  </p>
  
  <p>UPDATE: I tried starting ADB from the terminal again, and cannot recreate the conflicting version error. The server starts perfectly now.</p>
  
  <p>I was also having trouble with tunneling not working in Expo, so I've changed the host to localhost. It works, but I'm not sure exactly what the implications of this change are:</p>
  
  <p><a href="https://i.stack.imgur.com/4J8Yg.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/4J8Yg.png" alt="Expo host change"></a></p>
  
  <p>Obviously, I'm pretty new to Android development, and GenyMotion/Expo in particular. But I think I've been pretty thorough in my troubleshooting. What else can I try?</p>