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FactLockCam

THE ON-DEVICE EVIDENCE CAMERA

Anchor the original
before the story changes.

FactLockCam fingerprints photos and videos at capture, signs the record, and anchors it publicly—so a later altered copy cannot match the earlier record.

Verifies the exact file and signed record—not the physical truth of the scene.

  • SHA-256 FINGERPRINT
  • SIGNED MANIFEST
  • POLYGON ANCHOR
  • ZERO-UPLOAD VERIFICATION
Anchor your first capture Verify a proof package

iOS today. Android on Google Play at launch.

FactLockCam viewfinder on iPhone: live HUD with device clock, optional GPS, and the CHAIN LIVE lamp above the mechanical shutter

Anchor the Original. Verify it yourself.

See it in the app

Inside the app

A camera that writes the record as it captures

Screens from the shipping build. Every stage is on-device: the viewfinder, the sealed archive, the certificate, and the package you hand to a recipient.

  1. 01 · Capture

    Viewfinder with a live chain lamp

    The HUD shows the device clock, optional GPS, and whether the public anchor is reachable. Press the iris and the seal begins.

    FactLockCam viewfinder with a live chain lamp screen

  2. 02 · Archive

    Sealed items, fingerprint attached

    Each record carries its capture time, type, and size. Media stays encrypted on this device — only you hold the keys.

    FactLockCam sealed items, fingerprint attached screen

  3. 03 · Certificate

    Certificate Studio

    A printable summary of the fingerprint, device clock, capture window on Polygon, key class, and owner address.

    FactLockCam certificate studio screen

  4. 04 · Send Proof

    One password, one package

    Set a recipient password and share the .flcproof file yourself. The recipient unlocks it locally in a browser.

    FactLockCam one password, one package screen

Screens captured from the shipping iOS build on a developer account. Sample records shown; no customer data.

What it does

How it works

Three stages at capture, three separate results at verification. Nothing depends on trusting us.

  1. 01

    Fingerprint

    SHA-256 · exact bytes

    The instant you capture, FactLockCam hashes the exact media bytes. One changed byte produces a different fingerprint.

  2. 02

    Sign

    Canonical manifest · owner key

    A canonical capture manifest — fingerprint, length, MIME type, UTC metadata, key class — is hashed and signed by your key.

  3. 03

    Anchor

    Polygon · public record

    When the device is online, the manifest hash is published to Polygon. The transaction is the public reference a later copy is compared with.

Fingerprint. Sign. Anchor.

On-device evidence camera

Every photo and video is fingerprinted the instant you capture. FactLockCam signs that capture record and, when the device is online, publishes the record hash to an independent public ledger. Every signed record discloses how it was signed.

  • Exact-file SHA-256 fingerprint
  • Signed capture record
  • Public Polygon anchor when online

Change the file. Break the match.

Independent verification

Send a password-protected .flcproof package. Recipients open it locally in a browser—nothing uploaded—and check the file, the signature, and the public record as three separate results.

  • Zero-upload browser unlock
  • File, signature, and chain checked separately
  • A changed copy will not match this record
Read the full mechanism What a passing check does not show

Change the file. Break the match.

One byte changes everything.

The fingerprint of the original is fixed in the signed record. Edit a pixel, re-save the file, or strip metadata and the new fingerprint diverges immediately. The verifier does not judge how the image looks — it compares bytes with the earlier record.

Run the live challenge
Fingerprint comparison Illustrative

Original · recorded at capture

9f2c7e1a4b8d03e6c5a1f7d29b4e6c8a0d3f5b7e9c1a2d4f6b8e0c2a4d6f8b1e

Altered copy · inspected later

9f2c7e1a4b8d03e6c5a1f7d2e07c3a5f9b1d8e2c4a6f0b3d5e7c9a1f2d4b6e8c

media_hash_mismatch Divergence from character 25 of 64

Verify it yourself

Fingerprint any file. Right here. Nothing leaves this page.

Drop a photo, a PDF, anything. Your browser computes the SHA-256 fingerprint locally with WebCrypto — the same function FactLockCam runs at capture. Re-save the file with one change and drop it again: the fingerprint will not match.

  • Computed with window.crypto.subtle
  • No network request is made
  • Same SHA-256 the app records at capture
Local fingerprint SHA-256 · in this browser
File
Waiting for a file
Size
—
SHA-256
—
Time
—

This demo hashes the bytes you choose and keeps them in memory only. It is not a signed record or a public anchor — FactLockCam adds those at capture.

Why not the system camera

A normal photo gives you pixels. FactLockCam gives you a record.

Exact-file fingerprint at capture
System camera None. Any edit is invisible to the file itself.
FactLockCam SHA-256 of the bytes, computed the instant you capture.
Signed capture record
System camera EXIF metadata, editable by anyone with a laptop.
FactLockCam Canonical manifest signed by your key; signing method disclosed.
Public reference
System camera None.
FactLockCam Manifest hash published to Polygon when the device is online.
Recipient check
System camera Take their word for it.
FactLockCam Three separate results in their own browser. Nothing uploaded.
Where the media lives
System camera Camera roll and whichever clouds sync it.
FactLockCam Encrypted on your device. FactLockCam cannot read it.

Verifies the exact file and signed record—not the physical truth of the scene.

Who it is for

Anyone who may have to show a photo to someone who doubts it

All use cases

Plans

Start free. Pay for seals, not for sharing.

A seal is one photo or video captured and recorded inside FactLockCam. Send Proof, certificates, and recipient verification are included on every plan and are never metered.

Compare plans

  • Free

    $0

    5 seals lifetime

    Try the full pipeline on your own incident.

  • Standard

    $2.99/mo

    10 seals per month

    For the occasional record that has to hold up.

  • Plus

    $5.99/mo

    20 seals per month

    For renters, owners, and small fleets.

  • Pro

    $12.99/mo

    Unlimited seals

    For adjusters, inspectors, and property managers.

  • Incident Pack

    $9.99

    10 seals that never expire

    One-time. Stacks with any plan.

Can you trust it

Never ask the market to trust a claim they cannot verify

FactLockCam is built so you do not have to trust us. Only you hold the keys. Recipients inspect a package locally. The signed record can be compared with a public Polygon transaction. Every signed record discloses how it was signed.

  • 01

    Only you hold the keys

    Media is encrypted on-device. FactLockCam cannot read your archive or reset a lost password.

  • 02

    Recipients inspect locally

    A .flcproof package opens in the browser on their own device. Nothing is uploaded to us.

  • 03

    Compare with the public record

    The signed manifest hash can be checked against a Polygon transaction anyone can look up.

Exactly what a passing check shows, and the notes professionals need, are published in the threat model and Terms of Service.

Threat model Privacy Terms

Questions

Straight answers

More in the support FAQ and the threat model.

01 Does a passing check prove what happened?
No. It shows that the inspected file matches the record made at capture, that the record was signed by the recorded key, and, when present, that the record hash appears in a public Polygon transaction. It does not judge the scene, a person, or a claim.
02 Do recipients need the app?
No. They open factlockcam.com/open in any modern browser, choose the .flcproof file from their own device, and enter the password you gave them. Nothing is uploaded.
03 Where are my photos and videos stored?
Encrypted on your device. FactLockCam does not keep a copy of your media and cannot read your archive. Only proof hashes and ledger metadata sync to the backend.
04 What if I capture with no signal?
The seal still fingerprints and signs the capture locally. The public anchor is published when the device is back online, and recipients can check the file and signature in the meantime.
05 What is on the public ledger?
A hash of the signed capture manifest. Not your photo, not your name, not your location. The hash is meaningless without the file it was made from.
06 Is FactLockCam an AI detector?
No. Detectors guess whether pixels look synthetic. FactLockCam compares a file with an earlier anchored record. Those are different jobs; ours does not drift as generators improve.

THE ON-DEVICE EVIDENCE CAMERA

Anchor the original before the story changes.

Free to start. Capture inside FactLockCam, keep the sealed original in your archive, and share a package a recipient can check themselves.

Anchor your first capture Verify a proof package