title: Know if my app is uninstalled
body: <p>After a lot of research, I got to a conclusion that uninstalls can't be tracked as "Package Removed" action is not broadcasted to all the apps except the one getting uninstalled. </p>
  
  <p>And then I found a way of tracking uninstalls. I saved all uninstall user information by <strong>Sending a GCM and getting "Not Registered" error in the response</strong>(GCM gives "Not Registered" error for devices with the app uninstalled). </p>
  
  <p>So now, when I installed <a href="https://play.google.com/store/apps/details?id=com.opera.max.global&amp;hl=en" rel="nofollow">Opera Max</a> app and uninstalled it, it opened a webpage asking for "Uninstall Survey". How could they have done that?</p>