Multiple Hidden Vaults: One Sign, One Vault

In sigil., each sign opens its own vault. Draw one sign and you get your everyday private photos; draw another and you get a completely separate vault with different contents and a different encryption key. The app never shows a list of vaults, so nobody looking at it — or at you using it — can tell whether there is one vault or seven.

How it works for you

You create a vault by choosing a sign on the 5×5 grid. That is it: no name to type, no folder to pick. Later, opening the app shows the same grid every time. Whatever sign you draw determines what opens.

Some ways people use it:

• By sensitivity. A vault for screenshots and receipts you would rather not have in Photos, and a separate one for medical photos or ID scans.
• By topic. ID documents in one vault, a work project in another. Our page on ID documents shows why that separation is useful.
• By person. On a phone that more than one person uses, each person can keep their own vault behind their own sign.
• As a cover. A vault with ordinary private-but-harmless content that you are willing to open in front of someone, while the sensitive one stays closed.

How it works technically

Each vault is encrypted with its own 256-bit key, and that key is unlocked only by that vault's sign, hardened with Argon2id and bound to the phone's secure chip; see pattern encryption for the details. Two consequences follow:

1. No index. The app does not need a table of "sign → vault" to work, so it does not keep one. A sign is checked by whether its key can decrypt anything, not by looking it up.
2. Vaults are independent. Knowing one sign tells you nothing about the others. Opening one vault does not reveal the existence, size, or contents of another.

Authenticated encryption is what makes this clean: a wrong key fails verification instead of producing garbage, so the app can tell "this sign opens nothing" without storing anything about valid signs.

Why "no visible list" matters

Most vault apps — including several popular ones — show folders or albums once you are inside. That is convenient, but it means anyone who gets past the lock sees the whole structure. Apple's Hidden album is a single, clearly labeled album (see why the Hidden album isn't really hidden).

When there is no list, the conversation changes. If someone pressures you to "open the app," opening one vault is a complete, honest-looking answer, and there is nothing on screen hinting at more. This idea is related to plausible deniability.

Honest limits

• Not invisible to forensics. The encrypted data occupies storage. A forensic examiner with your device may be able to see that the app holds more data than one small vault would explain. Hidden vaults are about not revealing structure in the app, not about defeating a lab.
• Not a legal shield. In some situations you can be legally required to provide access. Hiding vaults from authorities with lawful power to inspect your device may be illegal. See border crossings for a measured discussion.
• Memory matters. More vaults means more signs to remember. Keep your recovery phrase safe and offline.
• Shoulder surfing. If someone watches you draw a sign, they can open that vault. Draw out of sight.

Practical tips

• Make each sign distinct. Two signs that differ by one dot are easy to confuse — and easy for someone who saw one to guess the other. Check each with the pattern strength meter.
• Decide your vaults up front. Two or three vaults with a clear purpose each are easier to live with than many improvised ones.
• Keep the cover vault believable. If you use one vault as the one you are willing to open, put real, everyday content in it.
• Watch the free limit. On the free plan you have 1 vault; creating more (up to 7) requires Pro.

Combined with the decoy vault

Hidden vaults pair naturally with the decoy vault: a vault with harmless photos, opened by its own decoy pattern. If someone forces you to open the app, you draw the decoy pattern; it opens only the decoy and erases nothing, and since there is no list, your real vault simply stays hidden.

Plans

The free plan includes 1 vault plus the decoy vault, with 100 photos and documents and 10 videos per vault, and every feature: decoy vault, self-destruct, disguised icon. Pro unlocks up to 7 vaults, each with its own pattern, and unlimited photos and videos — €39.99 once, or €19.99/year. Details on pricing. To see how other apps handle multiple albums and decoys, compare sigil. vs Keepsafe or sigil. vs Private Photo Vault.