How to Sign a PDF on iPhone Securely for Free

Electronic signatures are digital versions of handwritten signatures, and adding them on an iPhone is quick and easy.

This guide shows you how to sign PDFs using the built-in Markup tool and a trusted free PDF editor, ensuring your files remain secure and private.

Tip: For highly confidential documents, such as legal or government files, opt for digital signatures for enhanced authenticity and tamper-proof security.

Sign a PDF on iPhone with a Free PDF Editor

PDFgear is a free PDF editor with powerful tools for signing PDFs and filling forms on iPhone. It offers four signature options: type, draw, upload an image, or photograph your handwritten signature.

Additionally, PDFgear supports flattening signatures, which merges them into the PDF as a permanent part of the document. This ensures the signature cannot be edited or removed, enhancing security and authenticity.

Here’s a video showing the steps to add a signature in a PDF on iPhone.

Step 1. Download PDFgear from the App Store. And open a PDF file with it.

Step 2. Tap “Edit” at the top of the screen, then use the toolbar to select “Fill & Sign”.

Step 3. Tap the “Signature” icon, select “Create Signature,” then place and resize it in the PDF.

Step 4. Flatten the signature by tapping it and selecting “Flatten Signatures” when the option appears.

This permanently embeds the signature in the PDF, preventing deletion or tampering.

Note: Signature flattening is irreversible. Be sure to back up your PDF or verify the signature carefully before proceeding with flattening.

PDFgear offers an iOS app and a web-based tool for signing PDFs on iPhone. Follow the steps below to sign PDFs online without downloading any software.

Sign a PDF on iPhone Online for Free

If you prefer a no-installation solution or frequently sign PDFs across platforms, PDFgear’s online PDF signer is an excellent choice.

It requires no registration, subscription, or advertisements.

Step 1. Open PDFgear’s online signer, and open your PDF.

Step 2. Tap “Annotation”, select “Signature”, and choose a full signature or initial.

Step 3. Create your signature and place it in a PDF.

Step 4. Click the three-dot menu and select “Download” to save the signed PDF.

However, PDFgear’s online signer supports files up to 50MB. For larger PDFs, downloading PDFgear is recommended. The iOS app also offers an additional feature to take a handwritten signature photo in real-time.

Sign a PDF Using Built-in Markup Tool

Markup is Apple’s built-in feature that allows you to quickly sign PDF forms directly on your device, eliminating the need for additional tools.

Here’s how to use it:

Step 1. Open the “Files” app and locate your PDF.

(Note: The Markup tool is also available in other Apple apps, such as Notes and Mail.)

Step 2. Long-press the PDF file, and when the menu appears, tap “Markup”.

Alternatively, tap the file to open it, then select the Markup icon (pen tip) in the top-right corner.

Step 3. Tap “+” at the bottom, select “Signature”, and choose a saved signature or create one with your finger or Apple Pencil.

Step 4. Tap “Done” to save your changes, then share your signed PDF via Messages, email, or other platforms.

FAQs

Can I Sign a PDF on iPhone With Gmail?

Yes, you can. Open the attachment in Gmail, tap the Share icon, select the Markup tool, and add your signature to the file. For detailed instructions on using the Markup tool, refer to Method 3.

How Can I Sign a PDF on iPhone for Free？

You can use PDFgear online PDF editor to sign PDF for free.

Open PDFgear online PDF editor > Upload PDF > Click “Add or Edit annotations” > Select “Signature” > “Add Signature” > Create a new signature > Place it in PDF > Download the PDF.

How to Fill in and Sign a PDF Form on iPhone？

Use PDFgear for iOS to fill out and sign forms effortlessly.

Simply download PDFgear, open your PDF, and tap on a fillable text box to type or check a box to complete the form. To sign the PDF, switch to Fill & Sign, tap the Signature icon, and select Create Signature. You can add your signature by typing, drawing, uploading an image, or taking a photo.

What Is the Most Recommended App that Signs PDF on iPhone?

The choice of application depends on your needs and preferences. Native tools like Files and Apple Notes are easy and fast. However, PDFgear stands out for its security and privacy, keeping your documents on your device and away from the cloud.

What Are the Differences Between Digital Signature and Electronic Signature?

There is a significant difference between digital signatures and electronic signatures. A digital signature uses advanced public key encryption technology to verify and authenticate digital information.

In contrast, an electronic signature refers to any signature created and applied electronically, rather than being written on paper.

The Bottom Line

There are several easy ways to digitally sign PDF documents on an iPhone. The built-in Markup tool is the simplest option for signing PDFs. However, PDFgear offers enhanced security to protect your data and provides additional editing features for a more versatile experience.