What does PassKit do?
It lets you create, distribute and update passes in the Wallet.
What is a pass and how do I make one?
It’s a digital representation of a ticket, loyalty card or similar. It’s constructed by signing a .json file and any resources it references into a .pkpass file.
This process can be done manually, but moving it to a server allows you to make dynamic passes which can be subsequently updated.
How do I sign a pass?
Firstly, you’ll need to create a Pass Type ID and download the corresponding certificate from the Apple Developer Center.
Apple provide sample materials showing how to both sign manually and implement a signing server here.
How do I distribute a pass?
Passes can be emailed or downloaded via a URL.