Download the Denny’s app for the iPhone or Android and you can earn free food for checking in. For your first check-in, you get a free soft drink or coffee. If you check in between 4:01 am and 7 am, you get a free soft drink or coffee. If you check in at 11:11 am or pm, you get a free Pancake Puppies Sundae. If you check in to 2 different locations within an hour, you get a free Milk Shake. There are other things you can earn in the app with a little more work as well.