When the smart phone revolution began five years ago, the National Security Agency began looking for ways to crack the myriad of devices that were hitting the market including iPhones, Android devices, and Black Berry devices. Black Berry devices were the most popular among politicians and business people at the time.
This information comes from leaked internal documents from former NSA contractor Edward Snowden. According to documents the NSA got in on the ground floor of targeting smartphones as they began to rise in popularity. Several NSA presentation slides from a 2010 report called "Exploring Current Trends, Targets and Techniques," also had disparaging things to say about Apple co-founder and CEO Steve Jobs and the legions of iPhone users.
One slide shows a picture of Apple CEO (now deceased) Steve Jobs with the caption, "Here's Big Brother." Another slide shows Apple’s paying customers and describes them as willing participants in their own downfall when it comes to privacy. One slide in the NSA presentation identifies them as "zombies."
Over the last five years the NSA has cracked mobile operating systems and eavesdropped on mobile communications, in the process acquiring private and sensitive images and data. The NSA also reportedly took advantage of the iPhone’s location bug, which enabled them to track people over extended periods of time before it was fixed by Apple in mid 2011.
Android was also focused on by the NSA; special teams of NSA agents began examining Google’s mobile operating system in 2010, according to documents. To what extent they used the knowledge they gleaned from those examinations was not disclosed.
You can read more about the NSA's long-running activities related to smart phones here.