Senator Jay Rockefeller (D-WV) continues to plant his flag squarely on the territory of online privacy. His latest play is to send a letter to Apple and Google asking them to prove that their mobile platforms don't violate children's privacy laws. Current law prohibits companies from collecting any data on children under the age of 13. He's not saying that the Android or iOS devices necessarily DO violate that law, he just wants it spelled out how they don't. This letter was sent in advance of hearings today on Capitol Hill held by the Senate Commerce Committee, which has had six of these hearings in the last 13 months.