Scan a Document With Your Phone (No App)

The reason to scan with the phone you already hold is that scanner apps have become a subscription business. Most popular ones upload every page to their servers, print a watermark across the free output, nag for a subscription and demand access to your whole photo library. A page in the browser needs none of that: it opens on an iPhone or an Android phone, you take or choose the photo, and the correction runs on the phone itself.

The process is deliberately manual in one respect. After the photo loads you place four markers on the corners of the paper, and from those the tool reshapes the photo into a flat rectangle, then applies a colour, greyscale or black-and-white treatment. The black-and-white mode is what turns a greyish phone photo into the crisp page an office, a bank or a visa centre expects. Add more photos and they become more pages of the same PDF, so a six-page lease becomes one file. Marking the corners yourself takes a few seconds longer than an app with automatic detection but gives you control when detection would guess wrong on a cluttered desk. The quality ceiling is the photograph: shoot from directly above, on a dark table, in even light without a shadow from your own hand, and keep all four corners inside the frame.