DirectTV Streaming - DirecTV DVR

For DirecTV TV services which include DVRs and receivers, DirectTV Streaming We just got our DirectTV and AT&T Internet installed and love it so far. I am a little confused on the iPhone DirectTV app. Is it possible, or not to access my DVR and watch recorded shows on my iPhone, using the DirectTV app when I am away from home and using the normal AT&T Wireless LTE data on my iPhone. I thought this was possible but my DirectTV app on the phone can't find my DVR?