Carrier billing lets you pay for apps, games, or services by adding the cost to...

https://www.pop-bookmarks.win/carrier-billing-lets-you-buy-apps-games-or-digital-content-and-charge-the

Carrier billing lets you pay for apps, games, or services by adding the cost to your monthly phone bill or subtracting it from your prepaid credit. It’s a simple way to make purchases without using a credit card