iCloud backup is a daily snapshot that runs when the device is on Wi-Fi, charging and locked. The default classes Apple holds keys for include the device settings, Home Screen layout, iMessage and SMS/MMS history (when iCloud Messages is off), Apple Watch backup, ringtones, visual voicemail, and most app data that the developer marked for backup. Photos go to iCloud Photos as a separate stream if the user enabled it; otherwise they sit inside the daily backup. Health data is encrypted with a key tied to the device passcode; Keychain uses iCloud Keychain Escrow with a per-account key that Apple holds in a Hardware Security Module but cannot extract without the user's iCloud password and the device passcode.
The end-to-end encrypted classes are the ones Apple cannot decrypt even when served a production order. The official Apple list, current to 2025, includes Keychain (passwords, payment cards), iMessage when both ends have 2FA enabled, Apple Pay information, Health, Home (HomeKit), Maps Favourites, Memoji, Payment Information, QuickType Keyboard Learned Vocabulary, Safari Bookmarks (under ADP), Screen Time, Siri Information, and Wi-Fi passwords. For each of these, Apple's production response to a valid legal demand is metadata only: account creation date, last sign-in, recovery contacts, and device list.
Advanced Data Protection, an opt-in feature since iOS 16.2 in December 2022, extends end-to-end encryption to the remaining classes: iCloud Backup itself, iCloud Drive, Photos, Notes, Reminders, Voice Memos, Safari Bookmarks, Shortcuts, Wallet Passes, and any iCloud-backed app data. When ADP is on, Apple's production response to even a valid Indian MLAT-routed warrant returns only the account metadata and an explicit "data is end-to-end encrypted" line. The user becomes the sole keyholder.
| Class | Default key holder | Under ADP |
|---|
| iCloud Backup |