Apple's iCloud Keychain stores login and payment information from your iPhone and iPad and syncs it across all your devices. If you're switching to a dedicated password manager, it might be best to turn off iCloud Keychain first.
iCloud Keychain is the default password manager on iPhone and iPad, and it appears every time you sign up or try to log in to a new website. The iCloud Keychain feature suggests you create strong passwords.
Disabling iCloud Keychain will disable all pop-ups and messages related to passwords on your iPhone and iPad.
See also: XSS flaw revealed in Apple iCloud domain
You can turn off iCloud Keychain from the Settings app. To get started, open the “Settings” app on your iPhone or iPad. If you can’t find it on the Home screen, swipe down on smartphone or tablet to use Spotlight search to locate the app.
See also: iPhone/iPad: How to close all Safari tabs at once
Then, select the Apple ID profile section from the top of the screen.
Here, select the “iCloud” option.
Scroll down and tap the “Keychain” button.
To disable the feature, turn off the “iCloud Keychain” option.
In a few seconds, the iCloud Keychain feature will disappear.
The next time you try to log in to a new website, you will no longer see the prompt to save your password in Safari.
See also: How to hide the Tab bar in Safari for iPad (or bring it back)
You can return to this menu to re-enable iCloud Keychain at any time. During the re-enable process, your iPhone or iPad may ask you to sign in to your Apple ID account and verify your device password.
Information source: howtogeek.com
