A recent report in TechCrunch has revealed that a number of companies use a service that allows 'session replay', which can effectively translate into recordings of what users do on their iOS apps. This data can include on-screen taps and text field inputs. Apple has responded by insisting that all developers disclose their use of these services.
https://www.notebookcheck.net/Apple-tells-developers-to-either-get-transparent-about-screen-recording-in-their-apps-or-get-out-of-the-App-Store.404061.0.html