sarah,
i APOLOGIZE!
i'm trying to reconstruct what i did. i think at some point, i saw the user_agent in the whos on-line page, and i then modified the create function within the order class with the following line:
'ord_user_agent' => substr(zen_db_prepare_input($_SERVER['HTTP_USER_AGENT']), 0, 254)
which now stores that information in the order table. (i modified the orders table using an sql statement to add this extra field.) i have not been doing anything with it, but i have stored it! which i suppose for me makes this plugin a little superfluous. although i am unclear if my regular expression search is more definitive than the mobile detect class.
in looking at the order table, i'm not sure there is anything else stored there that will indicate mobile or not. nor am i seeing an other table where one could gather this information. although it "might" be there.
given that information, i am not sure one could reconstruct mobile or not for older orders.
again, i apologize for leading you a bit astray!
best.