The ”Passwort“ app is not a password safe in a traditional sense, but a rather smart, deterministic password generator. It can be used instead of a password safe.
With the ”Passwort“ app, you don't need to save your login data (web address, username and password) for each web site.
How does this work? The ”Passwort“ app takes the web site name, the username and a master password to calculate a password, formatted according your settings.
With the same set of input values (web site, username, master password and format options), the app will always regenerate same passwords, even on different iOS devices. Since the master password is your secret, no one else can reproduce your passwords.