Apple brought huge JavaScript performance improvements to Mobile Safari in March of this year, but those benefits didn't extend to Web apps saved to a user's home screen. iOS 5 will remedy that ...

The researcher specifically says the JavaScript code does not mean our app is doing anything malicious, and admits they have no way to know what kind of data our in-app browser collects.

The researcher also examined in-app browsers for other apps like Instagram and Facebook Messenger, which don’t appear to track as much as TikTok.