Apparently, mobile access does not show up on the Individual student access reports at the present time.  A Canvas support agent told me that this was because the mobile app uses access token rather than web sessions.  This means that the student access reports are not showing the entire story when it comes to student access of course material.  PLEASE FIX THIS!  This is the only way I will know exactly whether or not individual students have accessed course lectures, assignments, and other material.