Electronic Signatures · 5 min read · Published 2026-09-03

How to Sign a PDF on iPhone or Android

Draw your signature with your finger on a phone or tablet, download a transparent PNG, and place it in a PDF without installing an app.

Create a digital signature online free

Sign from a phone browser, no app needed

A finger on a touchscreen is a better pen than a trackpad, so a phone is often the easiest way to produce a signature. Draw it in your mobile browser, download the transparent PNG, and place that image in the document. Nothing is uploaded and nothing is installed.

Draw your signature now

On an iPhone or iPad

Open the signature generator

  1. Open the signature generator in Safari and turn the phone to landscape for more room.
  2. Draw your signature with a finger or an Apple Pencil.
  3. Tap Download Signature; the PNG is saved to Files or Photos.
  4. Open the PDF in an app that can insert an image and place the signature on the line.

On an Android phone or tablet

Open the signature generator

  1. Open the signature generator in Chrome and turn the phone sideways.
  2. Draw your signature with a finger or a stylus.
  3. Tap Download Signature to save the PNG to your Downloads folder.
  4. Insert the image into the document with Google Docs, Drive, or a PDF editor.

Getting a clean line on a small screen

How to add the signature to a PDF · The complete signature guide

  • Landscape mode gives you two or three times the drawing width.
  • Draw slowly and use a thinner stroke; fast strokes look jagged.
  • Sign larger than you would on paper, then resize the image down in the document.
  • Clear and redraw as often as you like — there is no limit.

Draw your signature now — Digital Signature Generator