What is Passbook?
Passbook is an application in iOS that allows users to store coupons, boarding passes, event tickets, store cards, 'generic' cards and other forms of mobile payment.
What is PHP-Passbook library?
PHP-Passbook is a library for creating and packaging passes inside your application. Distribution of generated pass files can be done by attaching the file in an e-mail or serving it from your web server.