Is there any way to handle when my android **application** goes into background and back? 

I want to use notification service for a on-line game - I use a service, which shows an alert when something happens in the game. I want alerts to show only if my application is active (on the foreground), so I need to start my service when application goes foreground and stop it when application goes background.

Note that I cannot use Activity.OnPause/OnResume methods. I have many activities in my application, and if I'll handle OnPause/OnResume, it is possible in a moment, when a user swtches one activity to another, application will look like background, thorough it will be foreground actually