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

https://josuedumv023.tearosediner.net/how-did-carrier-billing-start-with-ringtones-and-games

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