title: Is checking savedInstanceState for null in onCreate a good way to tell if the device was rotated?
body: <p>There's stuff I'd like to do in my Activities' onCreate() method only if they're constructed the first time, not when the device was rotated (on configuration changes). Currently I'm checking the savedInstanceState parameter passed into onCreate() for this. If it's null, then it's the first time the Activity starts, else there was only a rotation.</p>
  
  <p>Is this a good and reliable way to tell this? Are there alternatives to this?</p>