20/11/2017 Development / java script
app.run(function($window, $rootScope) {
      $rootScope.online = navigator.onLine;
      $window.addEventListener("offline", function() {
        $rootScope.$apply(function() {
          $rootScope.online = false;
        });
      }, false);

      $window.addEventListener("online", function() {
        $rootScope.$apply(function() {
          $rootScope.online = true;
        });
      }, false);
});

In your controller $rootScope.online in your view {{online}}