is the code name for an IMSI-catcher(IMSI = International Mobile Subscriber Identity [wikipedia.org]), which is basically a fake cell phone tower sold by Harris Corporation to various law enforcement agencies. (It's actually just one of a series of devices with fish names -- Amberjack is another -- but it's the name used in the media.) What is basically does is trick nearby cell phones into connecting to it. Once that happens, the IMSI-catcher can collect identification and location information of the phones and, in some cases, eavesdrop on phone conversations, text messages, and web browsing.
Interestingly,
He has been remarkably consistent about his main point:
We have one infrastructure. We can't choose a world where the US gets to spy and the Chinese don't. We get to choose a world where everyone can spy, or a world where no one can spy. We can be secure from everyone, or vulnerable to anyone.