Are photo vault apps safe? What to check before you trust one

The short answer

A vault app is safe when the files on the phone are encrypted with a named algorithm, the key never leaves the phone, and the developer's privacy label does not link your photos to you. Few apps in the category meet all three. Most give you a lock screen, which stops a casual glance and nothing else.

Hiding is not encrypting

Every vault app moves photos out of the camera roll. That is hiding. It protects you from someone swiping through Photos. It does nothing if the person has your passcode, connects the phone to a computer, restores a backup, or gets at the storage another way, because the files are still ordinary files.

Encryption changes the file itself. A properly encrypted photo is noise without the key, wherever it ends up. That is the difference between a lock on the door and a room with nothing readable inside it.

Five checks on the App Store page

1. Is the algorithm named?

Search the description for the word encryption. If you find AES-256-GCM or another named algorithm, the developer has made a testable claim. If you find military-grade, bank-level, or advanced security with no name attached, treat it as decoration. If the word does not appear at all, assume the files are stored in the clear.

2. Where does the key come from?

An app that encrypts on the phone should say the key is derived from your passcode, pattern or phrase, and that the developer never holds it. An app that says its cloud is encrypted with your password is telling you about the cloud, not the phone.

3. What does the privacy label say?

Every App Store page has a privacy label written by the developer. Three sections matter: Data Used to Track You, Data Linked to You, and Data Not Linked to You. If User Content (Photos or Videos) or Identifiers appear under Data Linked to You, the developer has told you that your photos are associated with your identity in their systems. If anything appears under Data Used to Track You, the app shares that data with advertisers or data brokers.

4. Does it need an account?

An account is a server. A server is a copy of something about you: an email, a device ID, and often the photos themselves. A vault that works with no account cannot lose what it never had.

5. What happens when you forget the code?

There are three honest answers. Recovery through the developer means the developer can get in. Recovery through a phrase only you hold means no one else can. No recovery at all means the files are gone. Any of these can be acceptable. What you want to avoid is an app that does not say.

What about the disguise?

Calculator icons, camera disguises and fake crash screens hide the app from someone looking at your home screen. They do not hide it from Settings, where iPhone Storage lists every app by name, or from the App Library. They also do not change what is inside the files. Disguise is a convenience, not a security property. More in calculator vault apps.

What happens when someone is holding your phone

This is the case the marketing skips. If someone demands you open the vault, a lock screen cannot help you. Three things can.

• A decoy vault. A second passcode opens a separate vault with its own albums. You open it, they see what you chose to put there.
• A self-destruct passcode. A third passcode erases the vault. Rare, and worth asking for.
• An intruder record. Failed attempts are logged, so you know it happened.

Kryptis has all three. Of the ten most-rated vault apps, Privault has a decoy folder and an erase-all passcode, Private Photo Vault, Secret Photo Album and Safe Lock have a decoy and break-in reports, Keepsafe has a fake PIN and break-in tracking on Premium, PV has a fake password, and the rest have a disguise or nothing.

How the popular apps score

Every row comes from that developer's listing or website. The detail is in the reviews and the comparison table.