With the Apple Card, Apple has created a credit card that lives entirely on your iPhone. Business Insider reviews some how this can make its use more secure and convenient, but also presents some limitations for mass adoption.
That approach is also what gives the Apple Card an edge over some rivals — the notion that anyone who has ever signed up for an email account can probably figure out how to apply for and use an Apple Card. Everything from activating your physical card to paying your balance relies on your iPhone, making the card feel as secure and familiar to use as any other Apple device.
https://www.businessinsider.com/apple-card-best-and-worst-feature-is-iphone-dependence-2019-8