The use of location-tracking ads targeted at Americans through smartphones and other devices poses a privacy and intelligence threat, according to the Army general nominated to be the next head of the National Security Agency.

“Ten, 15, 20 years ago we were concerned about what we said on phones. Today, we’re concerned about what our soldiers wear, where they are talking, where they are able to be monitored,” Lt. Gen. Paul Nakasone told the Senate Intelligence Committee on Thursday.