Something's changed with GTV the past few days regarding viewing PDF's. I used to read PDF's via the Docs Viewer app. Now, when I download something, I get the message "Whoops, can't view that in Google Drive. If you want to view it, download this Lumin PDF Viewer". I'm not sure that I want to use that app. Why can't I use the Docs Viewer app? Edit: The subject line should say Lumin File Viewer, not Lumin File.