title: How App in background can check for internet connection, IOS?
body: <p>My Iphone app have 2 mode, online mode, and offline mode. if user is using app in online mode, the request gets submitted to server immediately. if user is using app in offline mode, i will store the request locally, so that i can upload it when internet is available. I am using reachability class to check internet availability. Reachability is working fine with app.
  I am not able to achieve following scenario. I had stored request as user is working in offline mode, mean while user will push application  in background by clicking home button in iPhone. after some time user will activate the wifi or cellular connection in his device. when user enables internet connection, my app which is in background should get notified and should  start submitting  request to server. How can i achieve this functionality? Many ios app may be having same this requirement.  how they are doing it? any idea? </p>
  
  <p>I tried following step to achieve this, but wasn't successful.what  I am i doing wrong here, help me.</p>
  
  <p>1) I added observer for kReachabilityChangedNotification inside applicationDidEnterBackground delegate method. but my app fails to listen to the Kreachabiliychagednotification, in this method.</p>
  
  <p>2) If i add observer for kReachabilityChangedNotification inside applicationdidbecomeActive, then my app is able to listen for Kreachabiliychagednotification.</p>
  
  <p>Why IOS doesnt allow to listen for Kreachabiliychagednotification when app is in background? </p>