iOS 8 Today Extension not working on device

Question

When I run my Today Extension on the simulator everything works fine and it displays the following as expected:

Answer 1

The sources of my problems:

• on simulator viewDidLoad was called each time, on the device the view is loaded once and only viewWillAppear is called.
• the widget does not receive core data changes notifications
• do not call NCWidgetController.widgetController().setHasContent from widgetPerformUpdateWithCompletionHandler. The best place to use it (mostly) is your containing app, not the widget itself.

hope this helps someone