Pay-by-phone lets you buy digital products quickly by charging payments...

https://remote-wiki.win/index.php/What_Is_the_Confirmation_Step_in_Carrier_Billing_Checkout%3F

Pay-by-phone lets you buy digital products quickly by charging payments directly to your mobile phone bill or prepaid balance. This method removes the need for credit cards, making checkout faster and simpler—perfect for easy, on-the-go purchases.