Files with PKPASS file extension are used for distributing tickets, membership cards, coupons, or other loyalty packages. A dedicated application, called a wallet, is used to store generated data and allows users to access related accounts. PKPASS technology is not very popular all over the world.
PassWallet app technology (often referred to as Passbook) originated in the United States, where they were first introduced by Apple. All PKPASS files are digitally-signed by the issuer so any attempt to forge the data or access it without permission are deemed futile.