I'd encourage folks to get the mobile apps for McDonald's, Burger King, Wendy's etc. Lots of times, most of the time, there are deals/coupons that will get you food for cheaper, MdD's and BK also have a rewards system that earns you points towards free items.
Dairy Queen is another sneaky decent mobile app, they often have offers for mini or small Blizzards for a buck or two, ice cream cones too. And discounts on their food if you like it. I find their food really isn't for me (except their pretzel sticks with queso, those are pretty decent), but the ice cream is good.