I'm writing a personal financial app on iOS. It doesn't ask for any permission except Face ID usage (it uses Face/Touch ID to authenticate user). The financial data user input in the app never leaves user's device (the current version of the app doesn't access network). I know that Apple requires all apps should provide privacy policy, but I wonder what I should tell user. Should I tell user that my app collects user biometric identification and his/her financial data? That sounds too scaring. I have searched about this and read quite a few apps' privay policy but I don't see they mention that. So, is it OK for me to say in the privacy policy that the app doesn't collect any data from user?
One of the examples I found on the net is Ecquire. They claimed they didn't store user data. While I see their point, that seems an incomplete statement in a document like privacy policy because they did collect user data (otherwise how they get user's input?). Am I right? I'm really confused on these things. Thanks for any help.