Understanding TikTok: From viral teen videos to Chinese political censorship

This week, TikTok was in the news for pulling a video critical of China's mass detention of Uighurs. Most of the popular Chinese-owned social media app's users are children and teens who share lip-syncing videos, dance crazes and comedy skits. But in today's episode, Alex Hern, technology editor at the Guardian, explains why — behind the memes and music — there are some real concerns about censorship, privacy and foreign influence.