chainSign
Blockchain Document Proof
Free · In‑App Purchases · Designed for iPad. Not verified for macOS.
Capture any document — photo, scan, or file — and lock it to blockchain. Permanent, tamper-evident proof, verifiable by anyone, forever.
Every Document. Permanently Timestamped.
chainSign gives legal professionals a permanent, tamper-proof record that any document existed in a specific form at a specific moment — verifiable by anyone, forever.
Whether you're recording a deed, archiving an executed contract, or protecting an original work, chainSign creates a timestamped record on the blockchain that no one can alter or backdate. If a document's integrity is ever questioned, the record is one scan away.
WHAT YOU CAN DO
Register any document, photo, or text in seconds
Photograph signed originals and record them on-chain
Verify any record by hash or QR code — anytime, by anyone
Generate professional PDF certificates with a verification QR
Securely store originals with encrypted IPFS (optional)
Keep a complete history of every record you've made
HOW IT WORKS
Capture — Execute the document with your client and photograph the signed original (or upload text/PDF directly).
Record on Blockchain — chainSign permanently records the document with timestamp, block number, and transaction hash.
Receive Your Certificate — Download a professional PDF certificate with a QR code for your client's file.
BUILT FOR LEGAL PROFESSIONALS
Attorneys and law firms
Real estate offices
Corporate legal departments
Anyone who needs a verifiable record that a document existed in a specific form at a specific moment
TEAM-READY
Set up your practice with a Solo, Practice, or Firm plan. Invite team members by name and email, share an organization wallet, and centralize records across your office.
NO CRYPTO KNOWLEDGE REQUIRED
chainSign handles the blockchain for you. Behind the scenes, your documents are hashed and recorded on Polygon — a public, energy-efficient network with permanent, read-only records. We don't move your funds, we don't see your documents, and your private key is protected on your device.
PRIVACY BY DESIGN
Document hashing happens on your device
Wallet keys are stored & protected in iOS Keychain.
External wallets supported via WalletConnect (Rabby, MetaMask & more)
WHY BLOCKCHAIN?
Traditional records depend on filing cabinets and the companies maintaining them. E-signature platforms depend on a single vendor staying in business. Blockchain doesn't depend on either. Your record lives on a public, immutable ledger — verifiable by anyone, forever, even if chainSign itself disappears tomorrow.
IMPORTANT
chainSign is a blockchain timestamping and document-verification tool. It is not a notary public service and does not perform legally recognized notarization. chainSign records do not constitute legal proof, legal authentication, or admissible evidence in any jurisdiction. Users requiring notarization or formal legal authentication should consult a licensed professional in their jurisdiction.
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Subscriptions auto-renew unless cancelled at least 24 hours before the end of the current period. Manage your subscription in your Apple ID settings.
Terms: https://chainsign.pro/terms
Privacy: https://chainsign.pro/privacy
Support: https://chainsign.pro/support
Ratings & Reviews
- This app hasn’t received enough ratings or reviews to display an overview.
This update makes recording faster & smoother:
• Add documents straight from your Photo Library or Camera — not just Files
• Certificate & PDF downloads now work reliably, with clearer copy confirmations
• Subtle haptic feedback when a recording is confirmed
• History now refreshes automatically
• Easier keyboard handling & smoother navigation throughout
• Various stability & polish improvements
Thanks for using chainSign! Questions or feedback? Reach us at support@chainOpus.pro.
The developer, Demetrius Barrett, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Not Collected
The developer does not collect any data from this app.
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Seller
- Witty Inventions Digital, LLC
- Size
- 80 MB
- Category
- Business
- Compatibility
Requires iOS 16.6 or later.
- iPhone
Requires iOS 16.6 or later. - iPad
Requires iPadOS 16.6 or later. - Mac
Requires macOS 13.5 or later and a Mac with Apple M1 chip or later.
- iPhone
- Languages
- English
- Age Rating
4+
- 4+
- In-App Purchases
Yes
- Certified Hash Record $79.99
- Basic Recording $0.99
- Practice $699.99
- Solo $349.99
- Copyright
- © Witty Inventions 2026