title: how to avoid $diges on $rootScope?
body: <p>I'm developing a large mobile app that must works on prettty old devices. And I've met with a problem of long $digest time.<br>
  Could you give me an advice, how reduce it?<br>
  I was considering of calling <code>$scope.$digest()</code> instead of <code>$timeout()</code> to prevent firing  $digest on $rootScope and update only necessary $scopes and its childs when it's needed.<br> But there are another problem exist, I have to check $$phase every time when I'm calling $digest on $scope and it's looks oddly to me. I think that I'm doing something wrong.</p>