The iOS 17.4 version, currently available for beta testing, seems to include a new feature, "Virtual Card Number," for Apple Cash users.
According to some users on Reddit, Apple Cash users can now set up a virtual card number that can be used for purchases when Apple Pay is not available for online payments.
Apple Cash is Apple's prepaid card, which users have traditionally been able to use exclusively with Apple Pay, without any card number available. Money from an Apple Cash card can also be sent to friends and family, transferred to a bank, or applied to the balance of an Apple card.
With iOS 17.4, Apple is offering Apple Cash customers a new way to make online payments even if Apple Pay is not available. A new popup message in the Wallet app says:
"Set up Virtual Card Number. Keep your card information secure with a new security code for each transaction. Easily access this card number in Safari AutoFill and use it to shop online where Apple Pay is not available."
Once you opt to set up your Apple Cash virtual card number, you can view that card number, generate new card numbers, and security codes. This is essentially the same functionality available for the Apple Card credit card, introduced since its launch, now also available for the Apple Cash debit card.
Related: How to add bank cards to Apple Pay for Apple Watch?
Apple Cash is currently available in the USA, but Apple plans to expand this service to other countries.