title: Need some clarification about beta/alpha testing on the developer console
body: <h2>Background</h2>
  
  <p>The Android developer console has 3 tabs for publishing the app's apk file:
  alpha, beta and production, as shown here:</p>
  
  <p><img src="https://i.stack.imgur.com/Hsy2L.png" alt="enter image description here"></p>
  
  <p>as I recall from one of Google IO lectures, one cool way to check how good is your app before making a 100% scale publishing, is to allow only a percentage of the users to download the app first. I think it's called "staged rollouts" , because you can rollout the publishing in case it had too many problems to be published to all.</p>
  
  <h2>My question</h2>
  
  <ol>
  <li><p>What is exactly the difference between them, especially between Alpha and Beta?</p></li>
  <li><p>Only the production stage is available for people on the play store, right?</p></li>
  <li><p>which one/s allow to publish only to specific people/percentage , and in which way do you do it?</p></li>
  <li><p>which stage allows in-app billing, at least for testing ? I don't get why can't i test it out even before uploading the app.</p></li>
  <li><p>in the percentage method, if I publish a new app version using the same way, will it first update for the people who were lucky enough to install the previous version?</p></li>
  </ol>