You could extract the barcode at all times in the future by setting the system clock (you can do this on non-rooted phones, and keep it that way at least if you

You could extract the barcode at all times in the future by setting the system clock (you can do this on non-rooted phones, and keep it that way at least if you do it in airplane mode). The Android docs mention a "secure timer" in the hardware security module, but I'm not sure that it can be used to prevent this. https://developer.android.com/reference/android/security/keystore/KeyGenParameterSpec.html https://developer.android.com/reference/android/security/key...