Are there any parental control systems for Internet access via 3G mobile phones?

Almost all mobile operators offer a parental control system for mobile browsing. The systems give you a choice between several levels of control. In general, the first level blocks mobile access to adult social networking sites. The second level also blocks access to chat rooms and blog services. In addition to browsing, other mobile services might be limited by parental control, such as Instant Messaging, email, SMS etc..
For more information, contact your service provider.