Tuesday is one of the cheesiest days of the year.
Sept. 18 is the made-up holiday of National Cheeseburger Day, and restaurants are celebrating with discounts and free burgers.
Download the chain’s new Wayback App by Sept. 17 for a National Cheeseburger Day buy-one-get-one free deal Sept. 18. Also earn a free classic burger after making your first in-app purchase and earn other freebies.