title: How persistent is [NSUserDefaults standardUserDefaults]?
body: <p>I'm using [NSUserDefaults standardUserDefaults] for storing application settings.</p>
  
  <p>My questions are:</p>
  
  <ul>
  <li>do those settings are removed on app deletion?</li>
  <li>are they kept after an application update (through the
  AppStore)?</li>
  </ul>
  
  <p>Because I'm using it to store a password and don't want my users to reset them at each update. Also, I'd like that the only way to reset the password would be to remove the app and re-install it.</p>
  
  <p>Is NSUserDefault the right choice?</p>
  
  <p>Thanks,
  Jérémy</p>