Security

Security you can understand.

Here is VaultBolt's security model in plain language, including the threats it protects against and the limits no app can get around.

Every file is encrypted on your iPhone

VaultBolt seals file content, thumbnails and the vault index with AES-256-GCM authenticated encryption before anything is written to storage. Authentication means tampering or corruption is detected rather than silently accepted. Large videos are sealed in chunks so they can stream without decrypting the whole file.

Your unlock protects a random vault key

Each vault has a random 256-bit vault key. Your pattern, PIN or passphrase runs through Argon2id, a memory-hard key derivation function, combined with a secret held by the Secure Enclave, to produce a key that wraps the vault key. A stolen disk image cannot be brute-forced on a fast computer, because part of the key never leaves the device's secure hardware.

Recovery is in your hands

A 12-word BIP-39 recovery phrase derives a separate 128-bit recovery key that can unwrap the vault key. VaultBolt never stores it. Keep it on paper, away from the phone. Anyone with the phrase may be able to restore the vault; losing both the phrase and your unlock means nobody can.

Backups and shares carry only ciphertext

Encrypted backup goes to your private iCloud database. Planned sharing uses end-to-end encryption with the key in the link fragment or a phrase, never on our relay. Apple and VaultBolt can see that encrypted data exists and its size, not what it contains.

Hidden, decoy and duress vaults

VaultBolt tries every unlock slot in the same constant time, so a decoy or duress code looks exactly like a normal unlock. No screen lists or counts other vaults. A duress code removes the main vault's keys from the device within two seconds.

Locked means locked

Keys are dropped from memory when the app locks or goes to the background. The app-switcher shows a cover, screen recording is masked, and copied items are cleared from the clipboard.

Threat model

Who VaultBolt protects you from.

Who	Protected?	How
Snooper with your unlocked phone	Yes: Protected	Separate unlock, neutral icon, quick exit
Someone forcing you to unlock	Partly: Protected with Pro	Decoy vault and duress code
Thief with your locked phone	Yes: Protected	iOS data protection plus app encryption bound to the Secure Enclave
Forensic copy of the phone's storage	Yes: Protected	Secure Enclave secret prevents off-device guessing
Lab with the device and a jailbreak	Partly: Partly	Argon2id slows each guess; use a passphrase
Cloud provider or subpoena of iCloud	Yes: Protected	Only ciphertext under keys Apple does not have
Breach of VaultBolt's relay	Yes: Protected	Ciphertext only; keys never reach the server
Recipient who photographs a share	No: Not protected	No app can stop a second camera

What VaultBolt cannot do

Storage usage can hint that more data exists than the open vault shows.
Duress removes data on this device only; encrypted backups remain so you can restore later.
Nobody can prevent screenshots or photos of the screen. VaultBolt detects screenshots and tells you.
If you forget both your unlock and your recovery phrase, the data is gone. VaultBolt cannot recover it.
An independent security audit and a public whitepaper are planned before public launch.

FAQ

Questions, answered.

Is VaultBolt end-to-end encrypted?

Yes for backups and planned shares: content is encrypted on your device and only decrypted on your devices or your recipient's. End-to-end encryption does not protect a file you open on an unlocked phone.

Has VaultBolt been audited?

An independent audit of the cryptography and storage layer, with a public whitepaper, is planned before public launch.

Can VaultBolt recover my password?

No. There is no account and no back door. Your 12-word recovery phrase is the only recovery path.