I figured how to create a smart list to see which device someone used to view an email (Desktop, mobile, tablet...) however i have to create a seperate smart list for each type of device. I could just set the constraint to where device field "is not empty" and get a listing of all the devices in one view. However, when I do that and I try to display the field "Device" in the results page by editing the default view I don't see that we can display that field. Is this a short coming of Marketo or am I missing something?