title: android studio: release apk is not signed
body: <p><strong>* I have rephrased the post since originally posted *</strong></p>
  
  <p>When I try to run a just-built release apk, I get an error "the apk for your currently selected variant ... is not signed."  This is in the Edit Configuration popup.  Here are my steps:</p>
  
  <ol>
  <li>In the Build Variants tab, select "release"</li>
  <li>In the menu, choose Build -> Generate Signed APK</li>
  <li>In the popup, fill in the fields for the key store and passwords.</li>
  <li>In the second panel, change the destination folder to ...\app\build\outputs\apk (see note * below)</li>
  <li>Observe notification in upper right of studio: APK(s) generated successfully.</li>
  <li>In the menu, click Run -> Run App.</li>
  <li>I get an "Edit configuration" popup with the error "The apk for your currently selected variant ... is not signed.</li>
  </ol>
  
  <p>So, why this error?  The APK generated appears to be valid.  I have successfully posted it to the Android Store (alpha testing only) and verified that stack dumps are obfuscated.  </p>
  
  <p>What I can't do is download it (step 6 above) to my device.  I guess that's ok since I can download the debug version just fine.</p>
  
  <p>(*) Android Studio defaults the output for the release apk to a higher, presumably more convenient directory.  However I find it harder to manage the consistency of generated files when they are scattered about so I prefer all the generated apks in one place.</p>