While this app has a pleasant interface overall, it often breaks on my iPhone 12 Pro Max. I will be able to add items and check out, but attempting to pay will result in a vague error, forcing me to use the clunky mobile website to rebuild my order and pay. Also, the various customization options are all hidden in their own separate accordion menus, which makes it really clunky to modify several options at once. You might say this would take up too much space, but right now all the options and accordion menus use massive amounts of unnecessary padding and it definitely seems like most menu items’ options would fit onto a single screen. November 2021: I am unable to use the app OR website to pay via credit, debit, or Apple Pay. The only way for me to pay, besides going in person and waiting in line outside getting screamed at by tweakers. DoorDash Pickup allows you to order from Shake Shack and works well without much in the way of added fees, and it’s what I’d recommend using. Even if you’re currently able to pay, they’ll probably break it in a week again, don’t bother with this garbage app. Read recent reviews to understand how bad it is. November 28, 2021: Have a new phone. Tried the app again. Now it can’t even get past the “Choose a Shack” page. Once you “Choose a Shack”, and select indoor or walk-up pickup, the app hangs for a few seconds and then returns to the “Choose a Shack” page. At this point I’m actually enjoying seeing how this app can keep getting worse every week. December 2 update: I can once again use the app to order.