Carrier billing lets you buy apps, games, or subscriptions and have the cost...

https://andersonsimpressivecolumn.urbanvellum.com/posts/is-carrier-billing-the-same-as-paying-by-text-clearing-up-common-confusion

Carrier billing lets you buy apps, games, or subscriptions and have the cost added directly to your phone bill. If you’re on a monthly plan, the charges appear on your next statement