Purchase Blocker is a free feature that allows you to block a device on your account from buying premium content (e.g., apps, games, alert services, etc) that would be billed directly to your AT&T account. Purchase Blocker does not restrict credit card purchases from smartphone app stores.
Please note: Purchase Blocker is not compatible with AT&T Navigator and AT&T FamilyMap services. When Purchase Blocker is on, existing AT&T-billed premium content subscriptions (e.g., apps, games, alert services, etc.) will be canceled and one-time purchase attempts will be unsuccessful (including one-time charitable donations).