How to scan a document with your phone

What separates a scan from a photo

A photo of a document shows the table around it, the page as a trapezoid because the phone was held at an angle, and the paper tinted grey or yellow by the room's light and your own shadow. A real scan corrects all three: it finds the page's edges, straightens them back into a rectangle, and evens out the lighting so the paper reads as flat white.

On an iPhone

The Notes app has a scanner built in: open a note, tap the camera icon, then Scan Documents. It detects the page automatically, lets you adjust the corners, and saves as a PDF or images you can share from Notes. Files app also has a Scan Documents option under its "+" menu, which saves straight to a folder instead of a note.

On Android

Google Drive has a built-in scanner: tap the + button, choose Scan, and it works the same way as the iPhone version, saving the result to Drive as a PDF. Samsung phones have a similar scanner inside Samsung Notes. Stock Android without either app has no system-wide scan option.

Dedicated scanner apps

Adobe Scan and CamScanner both scan well and add automatic text recognition, but push a subscription for features like unlimited pages, no watermark, or exporting to Word. For an occasional scan, that is more than most people need to pay for.

Scanning a photo you already took, without an app

Stayput's document scanner tool takes photos you have already taken (from your camera roll, not live camera capture) and does the same correction in the browser: it finds the page's edges, straightens it, and lifts the shadows so the result reads like it came off a flatbed scanner. It works for a single receipt or a stack of pages combined into one PDF, with a choice of black-and-white, greyscale or colour output, and no upload, account or watermark. It needs the paper to be lighter than the surface it sits on so it can find the corners; the tool says when it could not detect a page and falls back to the whole photo, cleaned up.

Questions