title: apk does not install after generated by bundletool
body: <p>I followed <a href="https://flutter.dev/docs/deployment/android#build-an-apk" rel="nofollow noreferrer">instructions</a> to first generate app.aab per section <strong>Offline using the bundle tool</strong> , then, I am trying to generate the APK per <a href="https://developer.android.com/studio/command-line/bundletool#generate_apks" rel="nofollow noreferrer">Extract device-specific APKs from an existing APK set</a> and issued</p>
  
  <pre><code>java -jar .\bundletool-all-0.12.0.jar extract-apks --apks=.\samsung.apks --output-dir=.\my_samsung_APK_set.apks --device-spec=.\samsung.json
  </code></pre>
  
  <p>A folder is generated with name my_samsung_APK_set.apks and I can see multiple APKs there</p>
  
  <pre><code>base-arm64_v8a.apk
  base-en.apk
  base-master.apk
  base-xxxhdpi.apk
  </code></pre>
  
  <p>I copied these files manually on the phone and when I try to install base-master.apk by tapping on it, I get "<strong>App not installed</strong>", what is wrong ? I tried tapping on other 3 files and those gives error <strong>There was a problem parsing the package.</strong> .</p>
  
  <p>So which of these 4 files ( APK) is supposed to be tapped to install?</p>
  
  <p><a href="https://i.stack.imgur.com/dAY2O.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/dAY2O.png" alt="files that are generated"></a></p>