Don't know why McD's has a mobile app, but Chick-fil-A has an awesome one that lets you place an order remotely, drive into the designated parking spot, press a button, and get the food run out to your vehicle. It's a lot of fun.
Hehe. For what it's worth, the bugs aren't all worked out yet so you do have to walk into the building a lot to get your food. :P They also have it for dine-in customers.
