Just got back from Marathon Weekend, and randomly saw this getting breakfast at the hotel. Worked really well, was super useful!
Unfortunately, earlier in the trip I had the opposite experience at UOR. Placed an order at 11 at Minion Cafe, only to find out an hour later mobile order didn't work on their end and one single team member was taking orders manually going table to table (instead of in the order folks arrived). When a table of 8 got their meals before I got my soda cup, I knew something was wrong.
Anyway, I hate Uni mobile order.