The Emirati messaging app ToTok, advertised as an encrypted messaging service, is actually a spying tool used by the United Arab Emirates government. According to American officials familiar with a classified intelligence assessment and a New York Times investigation into the app, the UAE government uses the app to track every movement and activity of users who download it, who number in the millions. ToTok, branded as “fast and secure,” was downloaded from the Apple and Google app stores by users throughout the Middle East, Europe, Asia, Africa, and North America—though majority are in the Emirates. According to app rankings and research firm App Annie last week, ToTok was among the most downloaded social apps in the United States. ToTok is part of a digital arms race among authoritarian governments in their efforts to devise more sophisticated ways to track critics, members of the media, as well as foreign adversaries, and terrorist groups, the Times reports. The UAE, which is a close Middle Eastern ally to the United States, restricts functions of services such as WhatsApp and Skype.