Phasm

Hidden in plain sight.

Phasm turns ordinary photos into secret messengers. Your photo looks exactly the same — but it carries encrypted messages and files only someone with the right passphrase can reveal.

TWO MODES

• Ghost — Maximum stealth. Adaptive algorithms make hidden data virtually undetectable, even by statistical analysis. Deep Cover auto-activates for non-JPEG photos for ~43% more capacity. Supports file attachments.

• Armor — Maximum durability. Survives recompression, re-encoding, and mild cropping. Fortress sub-mode auto-activates for short messages and handles aggressive compression from messaging apps, including WhatsApp.

SERIOUS ENCRYPTION

• AES-256-GCM-SIV authenticated encryption — always on. • Argon2id key derivation — resists brute-force and GPU attacks. • Post-quantum safe — 256-bit symmetric keys. • No backdoors. No key escrow. You hold the only key.

PRIVACY BY DESIGN

• All processing on-device. Nothing is uploaded. • No account. No sign-up. No tracking. No ads. • Open-source Rust cryptographic engine — auditable by anyone. Standalone CLI tool (phasm) on macOS, Linux, Windows for automation and reproducible audits.

ONE PHOTO. MULTIPLE SECRETS.

Shadow Messages hide several independent messages in a single photo — each locked with its own passphrase. Send the same picture to five friends; each discovers a different message using their name as the key. Nobody knows the others exist. Under pressure to reveal your passphrase? Hand over the primary one. Shadow messages stay invisible — no header, no marker, no proof they exist.

MAGIC WAND

One tap silently tunes your photo for better embedding. Imperceptible texture is added to smooth regions like skies and bokeh — boosting capacity 10–35% with no visible change.

SHARE YOUR WAY

• Share via any app that handles images. • phasm.link — short links so recipients decode instantly in the browser or via App Clip / Android App Link. No install needed. • For guaranteed delivery through messaging apps, use "send as file."

AVAILABLE EVERYWHERE

• Native iOS app (iPhone + iPad) with App Clip. • Native Android app with App Links. • Web app at phasm.app — full encode/decode in the browser via WebAssembly, nothing leaves your device. • Open-source CLI for macOS, Linux, Windows — same engine, scriptable, ideal for automation and security research. • Supports JPEG, PNG, GIF, WebP, HEIC. • 15 languages on web, 38 on mobile.

HONEST LIMITATIONS

• Platforms that resize or re-encode photos may destroy hidden data. Use direct sharing or "send as file." • Capacity scales with image resolution. • Steganography hides the existence of a message. Encryption protects its content. Phasm gives you both.