I gave up on the app completely when I placed an order via the app, was waved past the payment window, then the order window denied it was placed (and paid for). I showed them the phone with the order number still on it. They said it could be a screenshot. After arguing for a while, I drove away without food.

I eventually got a refund after digging throw their web site for an email address, and emailed them the statement showing where it has been paid. With the back and forward while they asked for evidence, it took over an hour of my time in the end to get the refund. It wasn't the money. It was the principle.

The app is by far the slowest, most unreliable way to place an order with them. Period. The next slowest (although far better) is the kiosks. They also unreliable when the printer doesn't work (which is most of the time), and you make the mistake of forgetting the receipt number. Other fast food outlets have solved this problem by getting you to enter your name. That's beyond McDonalds apparently. The fastest, and most reliable way by far is to talk to a human.

The order should be the reverse. It is beyond me how they get it so badly wrong. Maybe price discrimination is the reason. Nothing else makes much sense for an organisation of the size and resources of McDonalds.