1. Passwords are safely protected with fingerprint, no one else can open the password book, fingerprint is checked in every sensitive UI.
2. Passwords are only stored on the device, no network backup, no privacy leaking.
3. Passwords are never shown in full strings at any given moment, which means someone stand nearby you can not see the full password strings.
4. If you device is lost, use "Find my iPhone" app to erase password data from the device, you can ensure that your passwords are safe from stolen.