PDF Security & Access Issues

How to Restrict Signature Features in PDF Forms on iPad and iPhone

Maira Mehtab Oct 18, 2026 869 views

Question details

The user wants to know how to restrict the signature function in a PDF form on an iPad or iPhone to force signers to draw their signature instead of using a saved one.

How to Restrict Signature Features in PDF Forms on iPad and iPhone

Product: PDF Reader
Device & OS: iPad and iPhone (iOS)
Scenario: Managing PDF signature permissions and forcing hand-drawn signatures on mobile devices.
Observed behavior: The fountain pen icon for the signature tool turns into a lock icon, preventing standard signature placement.

Before you start

Check if your PDF document currently has any password protection or security restrictions applied, as these settings dictate whether the signature tools are accessible or locked.

Solution 1Recommended

Apply PDF Security Restrictions

The lock icon appears because the PDF file has security settings applied. You can set up document permissions on a desktop application to restrict how iOS users interact with the file.

When a PDF is secured with a permissions password, features like form filling or signing can be locked. This is why the standard pen icon changes to a lock icon on an iPad or iPhone.

To replicate this and lock the document, you need to apply security settings before sending the file.

Open the PDF on a desktop editor

Launch your preferred PDF editor (such as WPS Office) on your PC or Mac and open the PDF form you want to restrict.

Access the Protect tab

Navigate to the Protect or Security tab in the top ribbon menu to access document permission settings.

Set a permissions password

Select 'Encrypt' or 'Restrict Editing' and enter a permissions password. Uncheck the option that allows filling in form fields and signing.

Save and share

Save the protected document and send it to the iPad or iPhone user. They will now see a lock icon instead of the signature tool.

Limitation on Forcing Drawing: There is no specific setting in standard PDF readers to force a user to use the 'draw' feature while disabling saved signatures. Securing the document simply locks the entire signing ability.

Solution 2

Guide Signers to Clear Saved Signatures

Since you cannot strictly force the drawing tool via document settings, you can guide users to clear their saved signatures so the app defaults to the drawing board.

Manage PDF Security and Signatures with WPS Office

WPS Office provides comprehensive PDF editing and security tools, allowing you to easily set document restrictions, protect forms, and manage signatures across all devices, including iPad and iPhone.

1. Install WPS Office: Download and open WPS Office on your computer, iPad, or iPhone.
2. Open your PDF: Load the PDF document you want to secure or sign.
3. Set restrictions: Go to the Protect tab and select Encrypt to set a permissions password and restrict unauthorized modifications.
4. Sign the document: If signing is allowed, use the Fill & Sign feature to draw a fresh signature.

Easily apply permissions passwords to restrict editing and signing.Use the Fill & Sign tool for custom hand-drawn signatures on mobile.Fully compatible with standard PDF formats and Adobe Acrobat security.Lightweight, cross-platform, and free to use.

microsoft office alternative - wps office

Frequently Asked Questions

Why is my PDF signature tool showing a lock icon on my iPad?

The lock icon indicates that the document has security restrictions applied by the author, preventing unauthorized modifications or signing.

Can I force a user to draw their signature every time on iOS?

Standard PDF viewers do not have a strict toggle to disable saved signatures. However, if a user has no saved signatures, the app will default to the drawing prompt.

How do I remove the lock icon to sign a PDF?

You must obtain the permissions password from the document owner. Once entered in the security settings, the PDF will be unlocked, and the signature tool will become available.

PDF Troubleshooting