Neuron Encrypt is a local file encryption app that keeps your files private. No accounts, no internet, no cloud — everything happens on your device. <b>Security</b> • AES-256-GCM-SIV (RFC 8452) — nonce-misuse resistant authenticated encryption • Argon2id key derivation (256 MiB memory cost) — GPU/ASIC resistant • HKDF-SHA512 key expansion with per-version domain separation • VAULTX04 format with authenticated header (AAD on every chunk) • 100% Safe Rust core — zero unsafe blocks in the crypto library • Zero internet permissions, zero storage permissions (uses SAF) • Keys and plaintext wiped from RAM with Zeroizing<T> on drop <b>Features</b> • Encrypt any file to a .vx2 container • Decrypt .vx2 files back to original • Batch processing — queue multiple files with one passphrase • Auto-detects encrypt vs decrypt mode from file magic bytes • Cancel mid-operation (within one 1 MiB chunk) • Password strength meter • Secure wipe original file after encryption (with confirmation) • Open source (GPLv3) <b>How it works</b> 1. Select a file (or drop one from your file manager) 2. Enter a strong passphrase 3. Tap ENCRYPT — your file is encrypted to .vx2 beside the original 4. Optionally wipe the original file Your passphrase never leaves the device. There is no recovery — if you forget the passphrase, your files are gone. This is by design. <b>Privacy</b> • No analytics, no tracking, no telemetry • No network permissions in the APK • No storage permissions (uses Android Storage Access Framework) • No backup (android:allowBackup=false) • Source code available at gitlab.com/theredhacker0345/neuron-encrypt <b>Technical specs</b> • Cipher: AES-256-GCM-SIV with BE32 streaming (1 MiB chunks) • KDF: Argon2id (m=256 MiB, t=3, p=4, 64-byte output) • RNG: OS CSPRNG (OsRng via getrandom) • Min Android: 7.0 (API 24) • ABIs: arm64-v8a, armeabi-v7a, x86_64, x86