Senator John “Jay” Rockefeller (D-W.Va.) asked Google and Apple whether their mobile applications and those of third parties partners are complying with child Internet privacy laws.

Ahead of a hearing Thursday on mobile device privacy, Rockefeller sent letters to Google, Apple and a trade group representing apps companies probing their privacy practices and asking whether they are seeking permission from parents for any information about youths under 13.

Many applications on the iPhone and Android phones appear targeted to children and routinely collect location, addresses, phone numbers and other personally identifying information. If those users are children, the Child Online Privacy Protection Act requires companies to gain parental permission before collecting that data.

In one letter to Apple CEO Steve Jobs, Rockefeller asked:

“Very little is publicly known about Apple-approved mobile applications that collect and use information about children in possible violation of” child privacy laws, he wrote. A similar letter was sent to Google Chairman Eric Schmidt.

The lawmaker asked whether Apple has produced its own apps that violate COPPA laws and if it requires third-party applications to comply with the law.

Officials for Google and Apple will appear at a hearing chaired by Rockefeller on Thursday on mobile privacy. Rockefeller said he would probe those representatives (neither Jobs nor Schmidt will appear at the hearing) to answer his question. The lawmaker has introduced a “do not track” bill that would block companies from following user activity online. In the House, Reps. Ed Markey (D-Mass.) and Joe Barton (R-Tex.) have introduced similar legislation aimed at children.

“New mobile technologies have put the world at consumers’ fingertips; however, many of those fingertips are still small and especially at risk of being exploited by companies that gather sensitive information from mobile devices,” Rockefeller said. “I am concerned that some applications running on today’s mobile platforms may be violating laws that are intended to protect children. My hope is that Apple, Google and the ACT can shed light on mobile app practices so that we can make sure children are protected.”

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