Carrier billing lets you buy apps, games, or digital content and charge the...

https://www.web-bookmarks.win/carrier-billing-lets-you-pay-for-purchases-using-your-phone-account-instead-of

Carrier billing lets you buy apps, games, or digital content and charge the cost directly to your phone bill. If you’re on a monthly plan, the purchase appears on your next bill. For pay-as-you-go users, the amount is taken from your available credit