For a few months, I tried to use it because there's a McDonald's on my commute home. I should be able to order before I leave work, pull into a parking spot, and someone should come out and give me my food. But payment on the McDonald's app is absolute trash, and I'm a noted dumbass.
I made the mistake of either mistyping my information or using an expired credit card. In that situation any app/website will tell the customer: "Hey idiot, your information is incorrect and you're a dumbass." But not McD's, the app just says there's a problem with the transaction and to check with the restaurant. It's real cryptic and made me believe that maybe their online payment system was down or my connection wasn't working.
One time, I wanted to order online so I could lowkey order 2 or 3 Happy Meals for some Mario toys they had. Because the app wouldn't explain that it was my card information, I went up to the drive thru to ask about the order. The damned app had placed four or five different orders, totaling somewhere around 10-12 Happy Meals.
Luckily that got straightened out.
Another time I tried to pay in the app and thought it was successful. I got to the first window, got a knowing glance from the cashier and continued driving forward. Except he hadn't finalized the sale yet and still needed payment, but I had pulled too far ahead to reach back. I had to go back into the restaurant and work for 5-10 minutes to get everything sorted out.
Now I can't even use my account because I managed to softlock myself out of my account. The McDonald's app has this awesome bug when you try to delete the payment information from your account if there's only one card saved. Now it says "Invalid Payment Provider URL" whenever I try to add a new credit card to my account. But I guess it's safe from hackers?