Carrier billing lets you buy digital goods or services and charge the cost...

https://acornmetric.com/s/n-PmOV_QBxMH1OIRGl6Jn

Carrier billing lets you buy digital goods or services and charge the cost directly to your phone bill. If you have a monthly plan, the purchase shows up on your next bill. With pay-as-you-go, the amount is taken from your available credit balance