Study shows metadata provides more sensitive information than thought9
A study out of Stanford conducted by Jonathan Mayer and Patrick Mutchler called upon 546 volunteers to reveal just what information can be discovered from the metadata collected from your handset. Using an app created by Stanford called MetaPhone, the study shows that the metadata collected by the NSA is much more probing than the public believes it to be and can lead to inferences about medical conditions, firearm ownership and more. By using the information to infer what a person's medical condition is, the NSA can figure out which medications you use and could even take a guess about which Doctors you are seeing. Knowing whether or not someone owns a firearm could hep the agency conclude whether a particular person is a Republican or Democrat.
Judge Richard Leon, back in December, ruled in Federal Court that the NSA's actions were unconstitutional. He added that the "metadata from each person’s phone 'reflects a wealth of detail about her familial, political, professional, religious, and sexual associations.’" In other words, in the right hands, metadata can paint an extremely accurate picture of you.
source: WebPolicy, MetaPhone via Gizmodo