CalcVault: Secret Calculator

Protect your private photos, videos, confidential documents, and passwords behind an authentic, fully functional mathematical calculator. CalcVault looks, acts, and calculates exactly like a sleek everyday calculator. But when you enter your confidential master PIN and press the '=' key, it instantly unlocks a fortified vault safeguarded by military-grade AES-256-GCM encryption. Zero accounts. Zero cloud servers. Zero tracking. Your data stays 100% on your device, always under your control. ━━━━━━━━━━━━━━━━━━━━━━━━━━━━ 🔒 FORTIFIED ENCRYPTION & PRIVACY ━━━━━━━━━━━━━━━━━━━━━━━━━━━━ • AES-256-GCM Encryption: Every single image, video, and text note is locked with an authenticated 256-bit encryption key and a unique random nonce. • Hardware Keystore Protection: Your master encryption keys are derived using 120,000 PBKDF2-HMAC-SHA256 iterations and stored directly inside your device's hardware-backed Keystore / Secure Enclave. • In-Memory Decryption: Media files decrypt solely in temporary RAM. No decrypted copies are ever written to your internal storage. • 100% Offline & Private: No Internet permission (android.permission.INTERNET is completely removed in release builds). No telemetry, no background sync, no analytics, and zero external trackers. ━━━━━━━━━━━━━━━━━━━━━━━━━━━━ 🎭 STEALTH DUAL-PIN DECOY VAULT ━━━━━━━━━━━━━━━━━━━━━━━━━━━━ • Real Working Calculator: Performs arithmetic calculations, percentages, square roots, parentheses, and trigonometric functions with precision. • Dual-PIN Duress Safe: Create an optional secondary Decoy PIN. If someone forces you to open your vault, enter the Decoy PIN to open an isolated decoy vault with innocent files, leaving your real private documents completely hidden. • Anti-Snoop Screen Blocker: FLAG_SECURE prevents screenshots, screen recording, and recent app-switcher thumbnails across Android. ━━━━━━━━━━━━━━━━━━━━━━━━━━━━ 🚨 INTRUDER DETECTION & PANIC LOCK ━━━━━━━━━━━━━━━━━━━━━━━━━━━━ • Break-In Intruder Selfie: Captures a photo of unauthorized intruders using the front-facing camera after three consecutive failed PIN attempts (optional opt-in permission). • Panic Flip Auto-Lock: In a hurry? Simply flip your phone face-down to return instantly to the calculator screen and lock down your vault within milliseconds. • Auto-Lock on Background: Leaving the app or turning off the screen immediately purges decrypted memory and seals the vault. ━━━━━━━━━━━━━━━━━━━━━━━━━━━━ 📁 COMPLETE MEDIA & CREDENTIALS LOCKER ━━━━━━━━━━━━━━━━━━━━━━━━━━━━ • Photo & Video Vault: Organize private pictures and home videos into custom encrypted folders. • Secret Password & Card Manager: Store payment cards, login credentials, PINs, and secure recovery notes. • Encrypted Voice Memos: Record and play confidential audio notes securely on-device. • Non-Destructive Import: Safely import from your photo gallery with an optional prompt to remove the unencrypted original. Experience genuine privacy with CalcVault. Your secrets remain yours alone.