A few updates ago they overhauled the app which now causes it to be very laggy and crash very often. Sometimes the crashing causes your cart to clear, which is extraordinarily frustrating when trying to put together a group order. This happens on new hardware on the latest version of Android and there's no real excuse for it. The app is at least usable, if you do everything efficiently and make your order quickly you can usually get it done before the app crashes itself.