S.I.G. Personal — Your Personal Data Vault

S.I.G. stands for Secure Identity Guardian — your digital guardian that protects your most sensitive data. Not a cloud service. Not a subscription. A vault that belongs to you alone.

S.I.G. Personal encrypts your files directly on your Android device. Documents, photos, passwords, personal records — everything meant for your eyes only.

Completely offline
The app requires no internet connection and no server. No registration, no account, no cloud required. Your data never leaves your device unless you explicitly choose to share it.

Three-factor protection
Your vault is secured by three independent factors: your personal certificate (Certificate.bin), your individual master key (Masterkey.json) and your password. All three must be present to gain access. Losing even one factor means permanent loss of access — even for us.

Your personal key
Every S.I.G. package is unique. The master key is calculated exclusively for you and is mathematically bound to your certificate using a multi-step cryptographic derivation (Collatz resonance + HKDF + AES-GCM). No other certificate — and no other version of the app — can open your vault.

The .spv file format
Encrypted files are stored in the proprietary .spv format (Secure Personal Vault). Internally, each file uses the SIG2 binary structure: a cryptographic header containing vault fingerprint and file index, followed by AES-256-GCM encrypted content blocks. This format cannot be opened by any other application, cannot be reverse-engineered without all three access factors, and contains no metadata that could identify the owner.

One-time purchase — no ongoing costs
S.I.G. Personal is a one-time purchase. No subscriptions, no hidden fees, no feature locks.

S.I.G. Personal as a password manager
Unlike well-known password managers, S.I.G. Personal stores your credentials exclusively on your device. No provider, no data center, no sync. Your password safe truly belongs to you.

Why not a cloud password vault?
Cloud solutions are convenient — but a central server is also a central target for attacks. S.I.G. Personal takes a different approach: your personal vault exists only on your device. Even in the event of a provider data breach, your data is safe — because there is no provider who knows your data.

Encrypt files — easier than ever
Encrypt documents, photos and notes in just a few taps. No technical knowledge required.

What sets S.I.G. Personal apart:

✔ No account required
✔ No internet access needed
✔ No subscription
✔ No ads
✔ No cloud dependency
✔ No hidden costs
✔ Proprietary .spv format — readable only by you
✔ SIG2 binary encryption — AES-256-GCM with vault binding
✔ One-time personal key — mathematically unique
✔ Made and developed in Germany

Important notice
Leue Research Germany has no access to your data and cannot recover lost credentials. Please keep your access files (Certificate.bin, Masterkey.json, Password.txt) in a safe place. If you lose your certificate, master key or password, access to your encrypted data is permanently and irrecoverably lost.

Privacy made in Germany.
Developed and designed in Germany, following German data protection standards.

Leue Research

Additional Information