I guess we live in the Snowden era.
Ultraprivate Smartphones
Mobile phones for the consumer market that transmit minimal personal information. ... On January 21 a text message flashed on phones held by the protesters thronging Kiev’s Independence Square. Ukraine’s president, Viktor Yanukovych, was then still clinging to power and brutalizing opponents. The message—from the number 111—read: “Dear subscriber, you are registered as a participant in a mass disturbance.” ...... the NSA gathers huge amounts of information from cloud computing platforms and wireless carriers, including the numbers ordinary people called and the times they called them. Not only could the government be watching you: so could websites, advertisers, and even retailers trying to track your movements within stores. Modern smartphones and the apps running on them are engineered to collect and disseminate enormous amounts of user data—such as location, Web browsing histories, search terms, and contact lists. ....... Traditional crypto required the parties in an encrypted conversation to possess the same unique decoding tool (or “key”). The new approach was fundamentally different: it involved two mathematically linked keys, one private, the other public. Suddenly, applications such as digital signatures became possible. You could use a private key to “sign” a document; later, anyone else could use the public key to verify that you were indeed the author.