Apple now supports the ability for verifiable COVID vaccination cards to be added to iPhone via the Apple Wallet application. The digital COVID-19 vaccine passport could be useful for situations where you must show your vaccine papers to travel, cross a border, enter into a restaurant, enter a building, or other for example. Rather than carrying around a delicate piece of paper, you can just simply use your iPhone and have a verifiable vaccine record with you instead to serve as your vaccine passport.
The ability to add Covid vaccine cards into Apple Wallet requires the iPhone be running iOS 15.1 or newer, as older versions do not offer this capability.