I am developing an Android app, and thinking of using in-app purchase to unlock full features of the app.
I want the app to be fully functional even without an active internet connection as well if the user paid, so I don't want to rely on checking the in-app API to check whether they purchased the paid version or not.
boolean userPaid = true;
Could I use shared preferences or internal storage to persist this userPaid data after application close/destroy, and would this be a secure method of storing the data?