ScanLocker seals a document on the iPhone that photographed it.
You point the camera at a page and tap Keep. ScanLocker encrypts that page with 256-bit Advanced Encryption Standard in Galois/Counter Mode as it writes, files it in a folder you name, and holds the key in this iPhone's Keychain.
The four tabs
Scan
Tapping the camera photographs a page. ScanLocker finds the paper's edges, flattens the image to a rectangle, and offers to lift the colour cast that a kitchen table puts on a white document. Tapping Keep encrypts the result into the folder you have selected. You can also bring pictures in from Photos, and you can export a folder as a PDF.
Locker
The Locker tab holds text: a policy number, a door code, a recovery phrase, the name of the street your first school stood on. Each entry is sealed on its own. A Locker Page Pin guards the tab, and the app checks that pin against a PBKDF2 hash and a random salt.
Security
The Security tab reports what the app has observed about itself. It shows whether this process has opened an internet connection, and it notes the time of each copy you send out and each picture you save to Photos. The note carries the time and the action. It never carries what the item said.
Settings
Settings carries Face ID unlock, the Locker Page Pin, the sharing switches that decide which folders may release a copy at all, and the transfer to a new iPhone.
Moving to a new iPhone
Migrate copies your contents to a second iPhone running ScanLocker across a direct local link, with both phones in front of you. The two devices agree a fresh key over ephemeral Curve25519 for that transfer alone, and the payload crosses sealed under it. A recording of the link is of no use afterwards, because the next transfer agrees a new key.
Sending a copy out
A copy leaves this iPhone when you start one of three actions: sending an item through the iOS Share Sheet, saving a picture to Photos, or running the transfer above. Each one is a deliberate tap, each one is noted on the Security tab, and each folder can be closed to sharing entirely.
What ScanLocker cannot do for you. The key that opens your items exists on your iPhone and nowhere else. Zirkon LLC holds no copy of it. If you delete the app or lose the device, the contents cannot be recovered by us or by anyone else, so keep your own copy of anything you cannot afford to lose.
ScanLocker is built for iPhone and is being prepared for release on the App Store.