With iOS 12, there are a variety of new password features. For developers specifically, the new OS will be able to show passwords from third-party password manager apps in the QuickType suggestions on your device — using a new Password Manager API. Users will also be able to easily share passwords between their iOS and Mac devices if they’re nearby one another.
Apple has also increased security on creating passwords. If you’re creating a password that you’ve already used on another account, it will be flagged and remind you not to reuse a password. It will also automatically create a strong password for you and then store it in your Keychain.
Siri will be able to help you with passwords as well — but not yet. While there isn’t much information on how this feature will work, Siri will apparently be able to help you search for passwords in the future.
iOS 12 also brings autofill support for third-party password managers. Whenever a login requires two-factor authentication, the new OS will automatically fill in the six-digit codes you receive through SMS on your iPhone.