Apple's system for reading codes from their gift cards looks simple but, behind it, there's quite a bit of complexity. The simple process of holding a card up to a camera for the code to be read involves lots of validation and other steps to make the process as seamless as possible. Equinux wanted to create their own promo cards, using the same system, and went on a deep dive to reverse engineer Apple's system in making their own cards.
In a recent blog post Equinux started their effort by trying to identify the font Apple uses on their gift cards. It turns out it's not one of the regular fonts on your system. After a bunch of digging they tracked down the font.
They also found the size of the font, and the relative size compared to the surrounding box on a gift card was important.
The full article is worth reading and Equinux provides a Filemaker template for creating your own cards for customer promotions.