title: iOS9 socket connection killed when app is suspended even though app is registered as VOIP
body: <p>I have an iOS app which uses the VOIP property in iOS to have the socket connection maintained in the background. The app is not actually VOIP but I have used the property so that the socket connection is not killed when app is suspended. This worked just fine in iOS8. But while testing with iOS9, I can see that the socket gets killed a few min after the app is minimized and the device is locked.<br>
  If the device is not locked ie. I minimize my app and keep using the device, the socket connection is not killed.
  Have anyone faced such an issue. Is there any extra configuration required for VOIP apps in iOS9?
  Appreciate any help on this.</p>