Thanks for the information. Embedding a fixed decryption key is what I do. My app supports user send data to another phone using airdrop, and I encrypts the file when transferring it. However I don't encrypt data files on phones yet. BTW, in my app the data are owned by user, so it's fine if they take a screenshot or do whatever. My purpose is to prevent other people to look at the data.
Topic:
App & System Services
SubTopic:
Core OS
Tags: