Exit/Close app on Windows Phone

How to close application for Windows Phone quickly at once after browsing a few tasks?  Instead of pressing "back" a number of times. Do we have similar things like Task Manager back in WinMobile 6.5 for WinPh 7.5? So we know which apps running and switch off quickly.

The answer is:

Exit();


private void Exit()
        {
       while (NavigationService.BackStack.Any())
       NavigationService.RemoveBackEntry();
       NavigationService.GoBack();
        }