A lease, a letter from the dentist, a school form, a warranty card: the paper you need again is never the paper you can find. Your iPhone can turn it into a PDF you can keep, search and send. This guide walks through what makes a good scan, then how to scan documents with Scan Cat, our document scanner for iPhone.
Set up the page first
A good scan starts before you tap anything:
- Lay the page flat on a table rather than holding it. Flatten folds and curled corners.
- Use even light. Daylight from a window works well. Keep your own shadow off the page, and avoid a lamp right above it that leaves a glare.
- Use a plain, darker surface under the page, so its edges stand out.
- Hold the phone straight above the page, parallel to it, so the lines of text don't lean. Fill the frame with the page and leave a little margin.
Check every page
- One page per shot. For a document with several pages, scan them in order into one file.
- Crop to the page's edges and straighten it, so the scan looks like the paper and not a photo of your table.
- Pick a look that fits the page. Black and white suits plain text. Keep grayscale or colour for stamps, photos or highlighting.
- Zoom in and read the small print before you put the paper away, and keep the paper until you've checked the scan.
Name it so you can find it
"Scan 0042" is a name you'll never search for. Name a file by what it is and when: "Lease 2026", "Dentist letter March". Then group your files the way you'll look for them later: home, work, school, health.
Save it as a PDF, small enough to send
- Use PDF for documents, so all the pages stay together in one file that opens almost anywhere. Use JPEG only when someone asks for an image.
- Match the paper size to the original: Letter in the US and Canada, A4 in most other places.
- Mind the file size. Email and upload forms often set a limit. A smaller file is fine for reading on a screen; keep the best quality for printing.
Scan a document in Scan Cat
- Scan or import. In your library, tap Scan to use the document camera, or tap Import, then From Photos or From Files, to bring in photos and PDFs. You can pick up to 50 photos at a time. Pages are saved the moment you scan them.
- Fix the crop if you need to. On an imported photo, Scan Cat looks for the page's edges and, if it finds them, crops to them. Tap a page, then Crop, to drag the four corners onto the page's corners; a page photographed at an angle is straightened. Find page looks for the edges again, and Whole image keeps the full picture.
- Pick a look. Under Look, choose Original, Grayscale, B&W or Enhanced, and tap Apply to all pages to give every page the same one. Left and Right turn a sideways page. Filters never change your original pages, so you can always go back to Original.
- Add, reorder or delete pages. Inside a document, Add pages brings in more by scan, Photos or Files. To change the order or remove a page, tap More (⋯), then Reorder & delete pages.
Find it later
Scan Cat reads the words on each page on your device, so you can search them. New scans name themselves from their first line of text, and you can touch and hold a scan in your library to Rename it or give it Tags. The search bar looks through names, tags and the words inside your scans, and shows the line that matched. To see or copy the words Scan Cat read, open Recognised text.
Export, email or print
Open the document and tap Export, then pick PDF, JPEG or Text.
- Paper: A4, US Letter or Fit to scan.
- Quality: Small (email and forms), Medium (everyday sharing) or Best (printing and archiving). Each shows the approximate size of the whole PDF before you share, so you can judge whether it will fit an email.
- Searchable text: the recognised text is built into the PDF, so you can search, select and copy it in any PDF app.
- Password: turn on Password and type one, and anyone opening the PDF will need it. Scan Cat doesn't keep the password, so remember it.
Then tap Share PDF to send it to Mail, save it to Files or open it in another app, or tap Print. With Text, you can Copy all text to paste the words somewhere else.
Need to sign what you scanned? See how to sign a PDF on iPhone. Got a photo in HEIC that a form won't take? See how to convert HEIC to JPG on iPhone.
What it costs
Scanning, text recognition, PDF, JPEG and text export, password PDFs, print and share are free, with no watermark and no limit on how often you export. There's no subscription, no trial, no ads, no sign-up and no account. Scan Cat Pro is an optional one-time purchase that adds three extras: Fit under a size (pick 1, 5 or 10 MB and the PDF is made as sharp as fits, for email and upload forms), Combine documents (several scans into one, in the order you pick) and Lock with Face ID (Face ID or your passcode to open Scan Cat). More on the Scan Cat page.
Your scans are kept on your device and in your own backups unless you share, save or print them.
Quick answers
How do I scan a document to PDF on iPhone?
In Scan Cat, tap Scan or Import, check your pages, then tap Export and pick PDF. The words Scan Cat read are built into the PDF, so you can search it later.
How do I scan a document and send it by email?
Export it as a PDF, pick Small, then tap Share PDF and choose Mail.
How do I make a PDF smaller to email on iPhone?
In Scan Cat's Export, pick Small and check the approximate size before you share. With Pro, Fit under a size makes the sharpest PDF it can under 1, 5 or 10 MB, and tells you if a very long document still won't fit.
Can I scan documents on iPhone for free?
Yes. In Scan Cat, scanning, text recognition, PDF, JPEG and text export, password PDFs, print and share are free, with no watermark. Pro adds Fit under a size, Combine documents and Lock with Face ID.
Try Scan Cat
Try Scan Cat: free, no watermark, no sign-up → iyio.com/apps/scan-cat