How to sign a PDF on iPhone

The print-sign-scan routine exists because most PDF tools treat a signature as an event instead of a stroke. On iPhone, signing is a thirty-second task: draw once, place the signature on the line, export. This guide walks through doing it well — and privately.

What you end up with: A signed PDF, ready to send back, with your signature stored locally for next time.

  1. 1

    Open the PDF in the editor

    Bring the document into Paperly — from Files, Mail, or the share sheet — and open it. Find the page with the signature line before drawing anything; knowing where the signature lands changes how large you should draw it.

  2. 2

    Draw your signature

    Use a finger or an Apple Pencil. Sign at a comfortable, steady speed — very fast strokes look thin, very slow strokes wobble. Paperly saves the signature on the device, so this only has to go well once.

  3. 3

    Place and size it on the line

    Drag the signature onto the signature line and pinch to resize. Aim for the size a pen signature would naturally be — signatures placed too large are the most common giveaway of a rushed digital signing.

  4. 4

    Add the date and any initials

    Most forms want more than the signature: a date next to it, initials on each page, maybe a printed name. Add these as annotations in the same pass so the document goes back complete in one reply.

  5. 5

    Export the signed PDF

    Export flattens the signature into the page, producing a standard PDF that opens anywhere. Send it back through Mail or Messages, or return it to Files — the original unsigned document stays in your library untouched.

Worth knowing

  • An Apple Pencil produces noticeably more natural strokes than a fingertip — worth it if you sign weekly.
  • Check the signed page at full size before sending: alignment on the line and a consistent size read as professional.
  • Save one signature, not five variants — consistency across documents is what makes a drawn signature look deliberate.

Do it in Paperly

This guide follows the real Paperly workflow. The relevant features, if you want the details:

Next: How to scan documents on iPhone