https://www.theregister.co.uk/2020/01/02/us_army_bans_squaddies_from_using_tiktok_on_government_mobes/

TikTok is one of the fastest growing social apps, with more than 1.5 billion downloads. However, its Chinese origins have caused controversy in the US, leading some lawmakers to declare it a threat to national security. And now the US Army has banned soldiers from downloading the app on government-issued phones.

Speaking to Military.com, Army spokesperson Lt Col Robin Ochoa described the app as "a cyber threat".