MONEYWEB app instead? As popularity surges. Image: Brent Lewin/Bloomberg The encrypted messaging company Signal has long been popular with activists, investigative journalists, politicians and assorted law enforcement officials because of its emphasis on privacy and security. Its growth was steady â but slow. Then came Christmas break. Employees returned from the holidays to an unexpected surge in new users that overwhelmed Signalâs servers and sent engineers racing to increase capacity. INSIDERGOLD Subscribe for full access to all our share and unit trust data tools, our award-winning articles, and support quality journalism in the process. SIGN UP To view all features and options, click here.