Scanlet

Scanlet turns paper into a PDF on your phone, and that is where it stays. Point the camera at a receipt, a form or a page from a book, and it finds the edges, flattens the page, evens out the paper and hands you a file to share. Nothing is uploaded, there is no account, and it works offline. If you want the PDF to be searchable, it can read the text too, on the phone, in English and Slovak.

It is a web app you add to the Home Screen rather than something from a store. That was the point: no install, no tracking, no middleman between a piece of paper and the person who needs it as a file. The cost is that every bit of image work has to run in the browser, from finding a crumpled receipt on a wooden desk to building the PDF, which turned out to be most of the project.

I built it for a small group of people who scan the same kinds of documents every week, and tuned it on their paper: thermal receipts, forms with handwriting, the odd newspaper page. The detector has an evaluation set of photographs it has to keep passing before any change ships, which is the only reason I trust it.