In simple terms, it means what you say on your iPhone — or any GSM phone, which includes all phones on AT&T, T-Mobile, Rogers, and almost all phones internationally — can be intercepted, decrypted, and listened to if a person has several thousand dollars worth of equipment and the motivation to do it

Here’s a fun story. Police in Australia thought they were being mighty clever when they took over an “underground hacking forum.” (The forum is r00t-y0u.org, though it seems to be down right now.) One of the hackers on the forum then retaliated by breaking into police computers using a simple SQL injection. Security fail.