Video-sharing app TikTok has come to rival some of the world’s most popular social-media platforms in just a few years. WSJ looks at how Chinese startup ByteDance took TikTok to the masses and why it attracted regulatory scrutiny. Video/illustration: Jaden Urbi/WSJ More from the Wall Street Journal: Visit WSJ.com: http://www.wsj.com Visit the WSJ Video Center: https://wsj.com/video On Facebook: https://www.facebook.com/pg/wsj/videos/ On Twitter: https://twitter.com/WSJ On Snapchat: https://on.wsj.com/2ratjSM #WSJ #TikTok #China