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How to Write on a PDF on iPhone with The Best Tool (iOS 17 Compatible)

If someone sends you a PDF document on your iPhone and asks you to share your opinion on the content, it may make more sense to share your thoughts directly on the PDF. But how do you do that? To write on a PDF on iPhone, you will need a tool that is designed specifically for this purpose.

These tools provide you with a wide range of annotation tools that will make it easy for you to mark up certain aspects of the document and therefore give direct feedback. Here, we will be looking at one such tool and share with you how you can use it to write on a PDF on your iPhone.

The Best App to Write on PDF on iPhone

How successfully you write on a PDF depends on the app that you choose to use. One of the best is UPDF for iOS. This tool is specifically designed to manage documents like PDFs directly on your iOS device and will therefore have all the features you need to write on the PDF easily and clearly.

But unlike other PDF tools that only allow you to read and make small annotations, UPDF is a valuable solution for those who work with numerous documents. It is the go-to solution when you want to manage your documents like a Pro and therefore a must have for anyone who uses a lot of documents.

annotate pdf on ios

Here are some of its most notable features:

  • UPDF takes annotation to the next level. You can use its freehand drawing tool to add text, add notes, draw markups, highlight, or even underline the text. It is also a useful feature when you want to sign a PDF document.
  • This document management tool also makes it very easy to create a PDF in the first place. The built-in smart scanner can create a PDF document from a scanned photo, document, note, business card, receipt, and many more.
  • You can also use it to securely protect your PDF documents using high-level security features like Face ID and passcodes.
  • It is also by far the best option you have when you want to keep all your files organized and easily accessible. You can access and view all types of documents including PDF, PowerPoint, Word, Excel, and most image formats.

How to Write on PDF on iPhone and iPad

UPDF also has a very simple user interface, meaning that you can very easily write on any PDF even if you have never used a similar tool before. Here's how to do it:

Steps for Writing on a PDF on iPhone

If you are looking to add text to the PDF document, follow these steps;

Step 1: Open UPDF and then tap on the PDF document to open it.

Step 2: Tap on the "T" shape icon at the top and then tap the "T" button to add text.

Step 3: A text box will appear. Double-tap on it and then input the text you'd like to add.

add text to pdf on ios

Step 4: When you're done adding text, tap outside the text box to close it. Resize it or reposition it as desired and then tap "Save" to save the changes.

Steps for Writing Annotations on a PDF on iPhone

If your goal is to annotate PDFs, follow these steps:

Step 1: Tap on the PDF in UPDF to open it.

Step 2: Choose an annotation tool that you would like to use from the options available. Whatever tool you choose, you can change the color and style of the pen to suit your needs.

how to write on pdf iphone

Step 3: Apply the annotation however you want and then tap "Save" on the drop-down icon to save the changes.


This article has predominantly provided a complete review of writing on a PDF file on iPhone. With a focus on the application that helps you achieve it, you have surely learned the right way. UPDF for iOS provides a diversity of features which makes it a compelling option in such an environment. You should look for this application for writing on a PDF while staying on an iPhone.