Phasm: Steganography
Christoph Gaffga Utilities iPhoneiPadiPod touch
Phasm: Steganography is a free Utilities app for iPhone and iPad by Christoph Gaffga. Requires iOS 17.0. Updated March 17, 2026.
- Price
- Free
- on the App Store
- Size
- 21 MB
- Age 4+
- Updated
- Mar 17
- 2026 · v1.6
Screenshots
About Phasm: Steganography
Hidden in plain sight. Phasm turns ordinary photos into secret messengers. Your photo looks exactly the same — but it carries encrypted messages and files that only someone with the right passphrase can reveal. TWO MODES FOR TWO NEEDS • Ghost Mode — Maximum stealth. Advanced adaptive algorithms make hidden data virtually undetectable, even by statistical analysis tools. Deep Cover auto-activates for non-JPEG photos with ~43% more capacity. Supports file attachments alongside your message. • Armor Mode — Maximum durability. Your hidden message survives recompression, re-encoding, and mild cropping. Fortress sub-mode auto-activates for short messages and handles aggressive compression from popular messaging apps. SERIOUS ENCRYPTION • AES-256-GCM-SIV authenticated encryption — always on, not optional. • Argon2id key derivation — resistant to brute-force and GPU attacks. • Post-quantum safe — 256-bit symmetric keys remain secure against quantum computers. • No backdoors. No key escrow. You hold the only key. PRIVACY BY DESIGN • All processing happens on your device. Nothing is uploaded. • No account. No sign-up. No tracking. No ads. • Open-source Rust cryptographic engine — auditable by anyone. • Built for journalists, researchers, activists, curious tinkerers — or just for fun. ONE PHOTO. MULTIPLE SECRETS. Shadow Messages let you hide several independent messages in a single photo — each locked with its own passphrase. Send the same picture to five friends; each one 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. Your shadow messages stay invisible — no header, no marker, no proof they were ever there. MAGIC WAND — ONE TAP TO OPTIMIZE Tap the wand and your photo is silently tuned for better steganographic embedding. Imperceptible texture is added to smooth regions like skies, bokeh, and flat backgrounds — boosting capacity by 10–35% with no visible change. The photo looks identical. The math works better. SHARE YOUR WAY • Share via AirDrop, Messages, email, or any app that handles images. • phasm.link — generate a short link so recipients can decode instantly in the browser or via App Clip. No install needed. • For guaranteed delivery through messaging apps, use "send as file." BUILT FOR iPHONE AND iPAD • Native app optimized for iPhone and iPad. • Supports JPEG, PNG, GIF, WebP, and HEIC — auto-converted for embedding. • Real-time decode progress with integrity scoring. • 38 languages supported. HONEST ABOUT LIMITATIONS • Platforms that resize or re-encode photos may destroy hidden data. Use direct sharing or "send as file." • Capacity depends on image resolution — larger photos carry more data. • Steganography hides the existence of a message. Encryption protects its content. Phasm gives you both.
What’s new
Version 1.6 · Updated March 17, 2026
Shadow Messages Hide multiple secrets in one photo. Each recipient uses their own passphrase — nobody knows the others exist. Send the same picture to five friends, each discovering a different hidden message. Or use it for plausible deniability: reveal the primary passphrase under pressure while shadow messages stay invisible. Magic Wand Tap the wand icon to optimize any photo for steganography. Adds imperceptible texture to smooth regions like skies and backgrounds, boosting capacity by 10–35% with no visible change to the image. Performance & Stability Core engine improvements across the board.
App privacy
The developer, Christoph Gaffga, reported these privacy practices to Apple.
Data Not Linked to You
The following data, which may be collected but is not linked to your identity, may be used for the following purposes:
- Usage Data: Product Interaction
Used for: Analytics
Alternatives to Phasm: Steganography
Looking for apps like Phasm: Steganography? Here are 6 similar apps on the App Store. The highest rated is Stegg - Hide Photos & Text (5.0/5), and all 6 are free to download.
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Stego
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Stegg - Hide Photos & Text
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Steganography: Hidden Message
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SecretPixel: Encrypted Photos
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Underlayer
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BTWN – Hide Messages in Photos
| App | Rating | Price | Last updated |
|---|---|---|---|
| Phasm: Steganography | – | Free | March 17, 2026 |
| Stego | – | Free | Jun 15, 2026 |
| Stegg - Hide Photos & Text | 5.0 / 5 (6) | Free | Sep 28, 2026 |
| Steganography: Hidden Message | 4.1 / 5 (25) | Free | Sep 11, 2026 |
| SecretPixel: Encrypted Photos | – | Free | Jan 15, 2026 |
| Underlayer | – | Free | Aug 22, 2026 |
| BTWN – Hide Messages in Photos | – | Free | Feb 21, 2026 |