iCloud Security and Privacy Overview
The table below summarizes how your data is secured when using various iCloud features
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When you access iCloud services using Apple’s built-in apps (for example, Mail, Contacts, and Calendar apps on iOS or OS X), authentication is handled using a secure token. Using secure tokens eliminates the need to store your iCloud password on devices and computers. Even if you choose to use a third-party application to access your iCloud data, your username and password are sent over an encrypted SSL connection.
