hill. i guess you can opt out of being tracked but how realistic is that and what do apple and google execs have to say about the data collection? >> it's a big question. those are the exact questions that they're trying to kind of shed some light on, shine the splight on today. privacy issues as relates to the internet and specifically here, mobile devices. when you think of the vast amount of information that these devices collect about users and especially, as you noted, in light of the uproot that was caused when it was noted that some apple devices were collecting time stamped tracking locations of users without their knowledge, the chairman of this committee, they are here today and they want to ask tough questions and shed some light on where federal regulation is working and if it is working or if it's just kind of knot cutting it at this point. as chairman leahy said, digital age can do wonderful things for