Is there a way to do this without iterating through the List and adding the items to the ObservableCollection?
to clarify what Junior is saying (with an added example if you're using LINQ that returns an IEnumerable):
//Applications is an Observable Collection of Application in this example
List filteredApplications =
(Applications.Where( i => i.someBooleanDetail )).ToList();
Applications = new ObservableCollection( filteredApplications );