Apple includes iCloud Keychain service in iOS 7+ and OS X Mavericks v10.9. Here you find instructions to setup iCloud Keychain on iOS 7+ and Mavericks. The iCloud Keychain keeps saved usernames, passwords for applications, Wi-Fi networks, and credit card information which a user can access across all the Apple devices, which are approved once by himself, running over iOS 7.0.3, or latest OS X Mavericks or later.
All the information saved in iCloud Keychain will sync across devices over iOS 7+ and OS X Mavericks v10.9 for supported applications. As an example if you are using Safari, and you have saved your username and password via iCloud Keychain then it will automatically fills in your username and password on the sites you choose with this service, on iOS 7.0.3 or OS X Mavericks.
When you upgrade to iOS 7.0.3+, iOS setup assistant asks to setup iCloud Keychain, in case you skip the step at that time, then guide below will help you to setup iCloud Keychain on iOS 7.0.3 or later device.
Setup iCloud Keychain on iOS 7
Tap on “Settings” from the Springboard, and then select “iCloud”
Tap on “Keychain” under iCloud screen
Tap on ON/OFF slider followed by “iCloud Keychain” to switch it ON
A screen with two options will pop-up, on iCloud Keychain screen that asks to “Use iPhone’s Passcode as an iCloud Security Code” or “Create Different Code”, we continued with the second option
Create an iCloud Security Code, using four digits
Re-enter your iCloud Security Code
Provide your phone number that can receive SMS messages. This can be your own number or the number of someone you trust. This number will be used to verify your identity when using your iCloud Security Code. Select your “Country” first and then enter your phone “Number” and then go next
The iCloud Keychain setup is completed now
The iCloud Keychain is ON now on your iPhone over iOS 7.0.3 and it will start recording your usernames, passwords for your accounts.
Simply open Safari and go to a website where you have to provide username, password and see the iCloud Keychain popup screen will open with options either you Save Password in your iCloud Keychain to auto-fill on all your devices or not
Setup iCloud Keychain on OS X Mavericks
Click on “Apple” logo () menu > “System Preferences”, and then select “iCloud” from the list and select “Keychain”
Optionally, you can set a password to unlock your screen on sleep
Enter your Apple ID password to setup iCloud Keychain, and then follow the onscreen instructions to complete iCloud Keychain set up on OS X Mavericks, Mac
Approve Devices to Use iCloud Keychain
When you set up iCloud Keychain on an additional device using steps above, your other iCloud Keychain enabled devices receive approval notification messages. When you confirm approval, iCloud Keychain will start updating automatic sync on all of your devices.