https://wccftech.com/tiktok-caught-collecting-mac-addresses-on-android-without-user-permission/

As per a report from the WSJ, TikTok had been silently collecting Mac addresses from Android users to track them. This was against TikTok's own privacy policies, as well as Google's policies for Play Store apps.

TikTok collected millions of unique identifiers through this method, over a period of 18 months, without users ever opting-in or even being aware of what was happening. The company was concealing this practice by adding a layer of encryption so that Google does not find out. It only stopped this practice in November 2019, as per the Wall Street Journal. All this happened before the focus on TikTok's security and privacy policies started this year in the United States, but this news will still give more ammo to those who want to see the app blocked.