Trump's cyber advisor didn't know about Signal

If you pay attention to surveillance or cybersecurity, you've probably heard of Signal since the election, right? It's an encrypted messaging app, and it's popularity has climbed in the wake of a new presidential administration that looks like it will favor increased surveillance. It's one of those no-brainer downloads for anyone concerned about privacy. 

Which is why it's just perhaps maybe a little eyebrow-raising that former New York City Mayor Rudy Giuliani, who will advise President Donald Trump on the nation's cybersecurity policy, only recently heard of it.