Is the iPhone Hidden album secure?
The Hidden album got a real lock in iOS 16. But a lock is only as strong as who knows the code.
The short answer
The Hidden album is secure against casual snooping: since iOS 16 it needs Face ID, Touch ID or your device passcode to open. It is not secure against anyone who knows your passcode, and hidden photos remain in your iCloud Photos library. For those cases, use an app with its own separate lock and encryption.
What the Hidden album does
Hiding a photo removes it from your Library, Memories and widgets and places it in the Hidden album. Since iOS 16, the Hidden and Recently Deleted albums are locked by default and open with Face ID, Touch ID or your passcode.
Where it falls short
The lock is your device passcode. Partners, family members or anyone who has watched you unlock your phone can open the Hidden album.
If you turn off Use Face ID in Photos settings, both the Hidden album and Recently Deleted open without any check.
With iCloud Photos on, hidden photos are stored in your iCloud library with your other photos. They are end-to-end encrypted only if you have turned on Advanced Data Protection.
When it is enough
If you just want certain photos out of your main grid, and nobody else knows your passcode, the Hidden album is a fine free option.
When to use more
Use a vault app with its own lock if other people know your passcode, if you want separate spaces for different things, or if you want to store videos and documents with their own encryption.
In Hidegrid, each vault opens with its own pattern that is separate from your passcode, and files are encrypted with AES-256-GCM using a key derived from that pattern.