“TikTok iOS subscribes to every keystroke (text inputs) happening on third party websites rendered inside the TikTok app. This can include passwords, credit card information and other sensitive user data. … We can’t know what TikTok uses the subscription for, but from a technical perspective, this is the equivalent of installing a keylogger on third party websites…
In a response to Forbes, TikTok confirmed that the features to track users do exist in their code, though they denied using them.”