How to scan documents with your phone

You do not need a scanner to send a scan. You do need to avoid four specific mistakes, because a rejected upload costs you a day and a resubmission. This is the whole routine: set the camera up once, shoot the pages properly, put them into a single PDF in the right order, and check the size before you send it.

Set the camera up before you shoot anything

Two settings cause most of the trouble, and both take under a minute to sort out permanently.

HEIC on iPhone. Since iOS 11 iPhones save photos as HEIC by default. It is an excellent format that a great many upload forms and tools simply do not read, including this one. Fix it in Settings → Camera → Formats → Most Compatible, and every new photo is a JPG. If you have already taken the shots, do not attach the file directly — share it (AirDrop, Mail, or the share sheet into Files), which converts it to JPG on the way out.

Live Photos and HDR. Turn Live Photo off for documents: it saves a short video alongside the image and inflates the file. Heavy HDR processing smooths paper texture and can soften small print, which matters if the page will later be run through text recognition.

On Android the camera saves JPG by default, so there is usually nothing to change. Check that you are not shooting in a “Pro” or RAW mode, which produces files ten times larger for no benefit here.

Light, shadow and background

Unusable photos of paperwork nearly always fail in the same three ways, and none of them is about the camera.

Your own shadow. Standing between the window and the page puts a gray band across exactly the text you need. Move so the light comes past you rather than from behind you. Flat, indirect daylight is the best free lighting there is.

Flash on glossy paper. It produces a bright blind spot in the middle of the sheet. Turn it off and find better light instead; a desk lamp bounced off a white wall beats a direct flash every time.

Shooting at an angle. Hold the phone flat and directly above the page. A tilted shot gives you a trapezoid instead of a rectangle, and the text along the far edge goes soft.

Then one small thing that makes all the difference: put the page on a plain, dark surface. The contrast makes the paper edges obvious, which helps both you and any later cropping.

Shoot the pages in order, and check the corners

Sorting tiles afterwards works, but shooting in order is faster and less error-prone. A short discipline covers the rest:

• Photograph the pages one at a time, in sequence, without skipping ahead.
• Check that all four corners are in frame before you move on. A missing corner is usually a missing signature, stamp or reference number.
• Shoot a two-page spread as two separate photos, not one wide one, so each page becomes its own page.
• Tap the screen to focus on the text, and zoom in to confirm it is sharp. Blur does not recover later — no setting anywhere rescues an out-of-focus photo.
• Fill the frame with the page. Every pixel spent on your desk is a pixel not spent on the letters.

Turn the photos into one PDF

Sending five loose JPGs is a small disaster: they arrive out of order, the recipient's mail client sorts them by filename, one gets stripped by an attachment limit, and nobody can tell which photo is page two. One PDF fixes all of it at once — one file, one fixed sequence, one thing to attach. It also reads as a document rather than a photo album, which matters when a bank, a school office or a government portal is receiving it. Many of them accept PDF only.

Open JPG to PDF, add the images, and each one becomes a page. Two things are worth knowing before you save:

• The order on screen is the order in the file. Photos added in one go arrive in the order your file picker lists them, which is normally alphabetical by filename rather than the order you took them. Drag the tiles to correct it, and rotate anything sideways.
• Page shape follows the image by default. With “Fit to image” each photo's own proportions become the page, so nothing is stretched or cropped. If a submission demands uniform sheets, switch Page size to A4 portrait or landscape and add a small margin.
• Images are embedded as they are, with no second compression pass, so the pages stay as sharp as the originals and small print does not turn to mush.

Check the size before you send it

This is where phone scans catch people out. A current phone camera produces eight to twelve megapixels per shot, so six photographed pages easily come to thirty or forty megabytes — and email gateways commonly stop at twenty-five. Portals are stricter still.

Do it in this order: build the PDF, check that every page is the right way up and legible, and only then run it through Compress PDF. Compressing before you check means redoing the work when a page turns out to be blurry. If the margins are wide because you shot from too far away, Crop PDF trims every page at once and takes weight off with them.

One last option, if the recipient needs to search or copy the text rather than just read it: run the finished document through OCR. It recognizes the words inside your photographs and gives you text you can correct and save. Clean, well-lit, straight-on shots read close to perfectly; the badly lit angled ones you now know how to avoid do not.

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