title: Android app crashes when made some changes in database
body: <p>I have developed an android app which consists of database.When i install it on mobile it works fine for first time. when i do some changes in database and install it again without uninstalling the previously installed version, it crashes.</p>
  
  <p>Note:I don't want to uninstall my previous version because i want to retain previously stored data</p>
  
  <p>Any suggestions friends?</p>