Problem

I Need to Sign a PDF

Short answer: To sign a PDF on iPhone or iPad, open the document, place a handwritten signature with Apple Pencil or your finger, and export a flattened PDF. PDF JustFit includes signing and markup tools in the same app.

What this looks like

Signing a PDF used to mean printing, signing, scanning and sending. On iPhone and iPad the whole loop can happen on the device the document arrived on.

  • A contract or form has arrived and needs a signature.
  • You have no printer, or printing would be slower than signing.
  • You need to sign and return the document the same day.
  • You want the signature to be part of the page, not a separate layer.

Why it happens

  • A document that requires a handwritten signature.
  • A form that expects a name, date or role alongside the signature.
  • A workflow that requires the signed file to be returned as a PDF.
  • A recipient who will not accept a separate signature image.

How to fix it with PDF JustFit

  1. Open the PDF

    Load the document in PDF JustFit.

  2. Choose the signing tool

    Draw with Apple Pencil or your finger.

  3. Place the signature

    Position it on the signature line, and add text if the form requires a name or date.

  4. Review the page

    Check the signature sits correctly on the page.

  5. Export flattened

    Export a flattened, share-ready PDF in a single tap.

Frequently asked questions

Can I sign a PDF on iPhone?

Yes. PDF JustFit lets you place a handwritten signature with Apple Pencil or your finger and export a flattened, share-ready PDF.

What does a flattened PDF mean?

A flattened PDF has the signature and annotations merged into the page itself, so they travel with the document rather than sitting in a separate layer.

Keep your documents light, organized and private

PDF JustFit: Compress, AI Chat is available on the App Store for $9.99. Requires iOS/iPadOS 26.5 or later.