title: How to kill an Android activity when leaving it so that it cannot be accessed from the back button?
body: <p>In an given Android activity, I would like to start a new activity for the user at some point. Once they leave the first activity and arrive at the second, the first activity is stale and I want to remove it completely so it can not be accessed again from the back button.</p>
  
  <p>How is the best way to accomplish this? How do I kill or destroy this activity immediately after the user has launched the new activity?</p>