- Learn about the leading apps for highlighting and annotating PDFs on Android with advanced features.
- Discover the key differences and usage tips to help you choose the app that best suits your needs.
- Learn how to highlight and protect your PDFs from your mobile device, optimizing your productivity and sustainability.
The PDF format has become one of the most widely used across all sectors : education, work, and personal life. Its ability to preserve the document's original formatting, its small file size, and ease of sharing have led to its increasing use for reading, studying, and storing important information. In a world where more and more activities are being digitized, knowing how to highlight or annotate information in a PDF on an Android device has become an essential skill.
Many users are unaware that apps exist that allow them to underline, highlight, add comments, and customize PDF documents from their Android phones , making it possible to emphasize relevant information, create notes, and share them quickly and securely. It's no longer necessary to always rely on a computer or waste paper printing documents. This article presents the best apps for highlighting PDFs on Android , compiling complete and up-to-date information so you can choose the option that best suits your needs.
Why highlight and annotate PDFs from your mobile phone?
Document digitization is a constant trend. Highlighting and taking notes on PDFs from your mobile device offers flexibility that not only facilitates studying and working but also improves personal organization. Whether you're reviewing class notes, work reports, or e-books, doing so from Android allows you to:
- Highlight important information for future reviews, saving time on study or subsequent consultation.
- Reduce paper use, collaborating with sustainability and avoiding unnecessary printing.
- Edit, share, and synchronize documents in the cloud anytime, anywhere, increasing productivity and collaborative work.
- Protect and store safely all your files, avoiding accidental loss or misplacement.
Current applications include features such as highlighting, underlining, strikethrough, inserting comments, digital signatures, encryption, OCR, real-time collaboration, reading aloud, and much more, turning your mobile phone into a complete portable office.
Updated Guide: The Best Apps for Highlighting PDFs on Android
Below, we present the top apps for highlighting and annotating PDFs on Android, including key features that make them unique and useful . All the options have been selected based on a combination of quality, ease of use, popularity, and added value for different user profiles.
1.PDFelement
PDFelement is one of the most powerful and versatile tools for working with PDF files on Android. Its main appeal lies in its set of advanced features that are usually only available in desktop programs:
- Various annotation tools: You can highlight, underline, strikethrough, add comments, sticky notes, and custom markup.
- Advanced Edition: Allows you to edit text, images, links and manage pages (extract, rotate, delete).
- Digital signature and forms: Fill out, sign, and share forms from your mobile.
- OCR: Convert scanned images and documents into editable, searchable text (premium).
- Protection and safety: Add passwords and manage permissions to protect your PDF files.
- Compatibility and synchronization: It works with Android, Windows, macOS, and iOS, facilitating continuity between devices.
Its modern, clean interface makes it easy to access all features, and it's a recommended app for both students and professionals looking to take document management to the next level on their mobile device.
2. Polaris Viewer
Polaris Viewer has long been a favorite app for viewing and annotating PDFs on Android. Originally part of the Polaris Office suite, its specialization in document viewing and editing makes it extremely practical.
- Underlining, highlighting and editing texts in PDF and other popular formats (Word, Excel, PowerPoint).
- Intuitive interface which allows you to edit quickly even on devices with small screens.
- File management and organization in custom folders.
- Integration with cloud services to access your files anywhere.
Downloading it from Google Play is easy, and it's especially useful for those looking for a quick and efficient solution for marking, highlighting, and sharing relevant information.
3. PDF Reader
PDF Reader stands out for its ease of use and for being one of the most highly rated apps on Google Play, having been awarded as the best application in its category.
- Simple underlining and strikethrough with quick selection of color and line thickness.
- Allows add comments and notes in the margins, ideal for taking notes.
- Supports the reading in dark mode to reduce eye strain.
- Advanced file management including quick search and folder organization.
- Function for scan documents and convert them to PDF, making it easier to work with printed material.
This application is highly valued for its attractive visual design and agile user experience , making it an outstanding option for students and anyone who regularly handles PDF documents.
4. Xodo PDF Reader & Editor
Xodo PDF is one of the most comprehensive and popular apps, with millions of downloads and a very high rating on Google Play. It's ideal for reading, editing, and annotating PDFs.
- Advanced annotation tools: underline, highlight, strikethrough, freehand drawing, inserting sticky notes and shapes.
- Document management with support for editing, page rotation, file extraction and merging.
- Collaborative interface, allowing you to edit and comment on documents in real time with other users using Xodo Connect.
- Cloud Sync: Google Drive, Dropbox, OneDrive, etc., to work without limits from any device.
- Digital signature and completion of interactive forms.
Its main advantage is the integration of all editing and annotation functions under a very intuitive interface with stylus support, ideal for those who work in teams or want to centralize all PDF management in a single app.
5. Foxit PDF Reader Mobile
Foxit PDF is synonymous with speed and lightweight performance, making it the direct alternative to Adobe in the professional and business world. Its mobile version for Android is powerful and efficient.
- Underlining, highlighting, and quick annotations.
- Editing text, images and links within the PDF document.
- Cloud Sync and offline access to your files.
- Digital signature and password protection.
- Out loud reading and support for scanned files using OCR.
- Function for share and collaborate risk management.
Foxit PDF takes up little space on your device and doesn't require many resources, a safe bet for those looking for efficiency and security in their PDF files.
6.Adobe Acrobat Reader
Adobe Acrobat Reader is the world's leading PDF reader and editor. Its Android version is versatile and maintains the quality of the desktop version, offering:
- Underlining, highlighting, strikethrough, annotations and comments.
- Sticky notes, freehand drawings, signatures, and form completion.
- Advanced search and zoom tools to quickly find any data.
- Automatic synchronization with the cloud (Adobe Document Cloud, Google Drive).
- Protecting files with passwords and encryption.
- Advanced subscription features include text editing, PDF to Word/Excel conversion, and document scanning.
One of its great advantages is its universal compatibility and the ability to easily share documents between devices and users.
7.iAnnotate PDF
iAnnotate PDF is another go-to tool for making comprehensive annotations in PDFs, optimized for Android tablets and mobiles.
- Pen, underline, highlighter, and strikethrough tools to personalize your brands.
- Desktop-like user interface but adapted to touch screens.
- Home page with quick start guide for new users and contextual help.
- Cloud sync to access your files wherever you want.
- Optimized for tablets and mobile compatible.
What makes iAnnotate stand out is its balance between feature set and ease of use, ideal if you're looking for a free, professional experience on Android. You can safely download its APK.
8. Docusign
DocuSign is recognized worldwide as a leader in digital signatures, but it also offers tools for highlighting, annotating, and sharing PDFs.
- Underlining and basic annotations to highlight key information.
- Legally valid electronic signature for all types of documents.
- Cloud storage and synchronization, fast and secure access.
- Some advanced features are paid, but the free version is sufficient for regular use.
Ideal for those looking to manage and authorize documents from their mobile device with complete security and compliance with regulations.
9. PDF Max
PDF Max is considered one of the most complete applications for PDF annotation and editing on Android.
- Underline, highlight, comment, freehand drawing, and stamp tools.
- Creating handwritten notes and completion of forms, even non-interactive ones.
- Customization of color, thickness, size of the marks and undo/redo function.
- Text Reflow View and reading aloud.
- Cloud Sync y offline reading.
- Minimalist interface which facilitates intensive use from the mobile phone.
PDF Max is perfect for those who want a customizable and detailed experience when working with PDFs, including the option to sync to the cloud and create handwritten annotations.
If you're interested in this app for highlighting PDFs on Android, you can download it through the official website or alternative app stores.
10. UPDF for Android
UPDF is an app that has recently gained popularity for its variety of features focused on highlighting and annotating PDFs on mobile devices. It's ideal for both students and professionals.
- Advanced annotation tools: underline, highlight, strikethrough, wavy lines, sticky notes, shapes, and stickers.
- Robust file management: Easily move, copy, rename, delete, and duplicate PDF files.
- Split-screen reading mode to compare two documents at the same time.
- Sharing functionality: Creating shared links and controlling access permissions.
- Compatible with major cloud storage services.
- Freemium model free app, free of charge for basic functions.
One of its great advantages is its user-friendly interface, adapted to new users , allowing anyone to start highlighting PDFs from the first use.
11. PDF Editor: PDF Reader Viewer
PDF Editor is a smart assistant for editing, viewing, and managing PDF files of any type on your Android device.
- Underline and highlight with ease using the built-in editor.
- Sign, write and add annotations even with a brush in PDF documents.
- Combine, cut, and merge PDF files in seconds.
- Quickly view, organize, and search your PDFs thanks to advanced file management.
- Dark mode for more comfortable reading.
The app is ideal for both students and those who need to manage documents daily from their mobile phone.
12. PDF Reader Pro
PDF Reader Pro is an option that combines professional reading and editing functions with specific tools for highlighting and even document scanning.
- Underline, highlight and strikethrough in different colors.
- OCR Scan and editing PDFs created from images.
- Allows you to add stamps, signatures, images and comments.
- Visual comfort with different reading modes and quick navigation.
13.iLovePDF
iLovePDF is known for its web version, but its mobile app is one of the most complete when it comes to working with PDFs on Android:
- Underlining, comments, signatures and full text editing.
- Convert PDF to Word, Excel, PowerPoint with OCR technology.
- Compress, split, merge, and organize PDF pages.
- Security and protection with encryption and passwords.
Ideal for those looking for a comprehensive PDF editing and management experience from their mobile device.
14. PDF PRO
PDF PRO is a free application available for Android and iOS devices, very useful for those who need additional features when highlighting and annotating PDFs:
- Insert voice recordings and personalized stamps.
- Color labels and file organization by folder.
- Advanced text search and support for fast printing on compatible printers.
- Encryption and password protection of your PDF documents.
How to underline text in a PDF on Android? Step by step
Highlighting, underlining, or annotating text in a PDF is very easy with any of the apps mentioned. The process is generally similar in all of them:
- Open the application and locate the PDF file from local or cloud storage.
- Choose the underline or highlight tool in the toolbar or main menu.
- Choose color, thickness and style of the underline according to your preference.
- select the text that you want to underline by dragging your finger or using the pointer.
- You can add comments, sticky notes or drawings over the underlined area if the application allows it.
- Save the changes and share the file if necessary.
Some applications even allow you to export the list of notes and highlights, making it easier to create summaries or review content.
Advantages and differences between PDF highlighting apps on Android
Not all apps offer exactly the same features. When choosing the best app for you, consider these key criteria and differences :
- User interface: Opt for apps with intuitive menus and easy access to annotation tools.
- File Compatibility: Make sure it supports various PDF formats, scanned files, and protected documents.
- Customization options: Some apps allow you to adjust the color, thickness, opacity, and type of underline or highlight.
- Synchronization and collaboration: Choose apps that integrate with the cloud and allow for teamwork.
- Extra features: Look for OCR, page management, digital signature, secure sharing, document scanning, read-aloud, or AI integration to maximize your experience.
- Business model: Determine if the app meets your needs in its free version or if you will require premium features.
When to use each app? Recommended use cases
- Students: Xodo, PDFelement, UPDF, and PDF Max are ideal for highlighting, taking notes, summarizing, and collaborating on group projects.
- Professionals: Foxit PDF, Adobe Acrobat, iLovePDF, and Docusign stand out for their digital signature features, advanced organization, and document security.
- Occasional users or readers: PDF Reader Pro, PDF Editor, Polaris Viewer, and PDF PRO are perfect for those who prioritize simplicity, fast file management, and basic annotation.
- Educators and collaborative work: Xodo and PDFelement make it easy to share editing, comment, and provide real-time feedback.
Practical tips to get the most out of PDF highlighting apps
- Adjusts the underline color to differentiate types of information (for example: yellow for concepts, blue for dates, green for formulas).
- Use sticky notes to add definitions, examples or reminders next to the underlined parts.
- Sync your files to the cloud so you don't lose your notes and can access them from any device.
- Take advantage of OCR functions to convert scanned documents into editable and underlineable text.
- Protect your sensitive files adding passwords and restricting editing or printing permissions.
- Export annotations to create summaries or study more efficiently.
Frequently Asked Questions About PDF Highlighting Apps for Android
- What free app do you recommend for highlighting PDFs? UPDF, Xodo, and PDF Editor are free apps with all the basic features to highlight, underline, and annotate any PDF.
- Can I sign my PDFs from my mobile phone? Yes, most apps like Adobe Acrobat, Foxit, and Docusign allow legal electronic signatures from your mobile device.
- How do I highlight text in protected PDFs? If the file is protected, you'll need to have the appropriate permissions or decrypt the file first. Many apps offer limited support for protected files, and some include tools to unlock them (depending on local regulations).
- Is it possible to share my notes and highlights? Yes, apps with cloud integration and collaborative tools allow you to share documents with annotations and highlights visible to other users.
The range of apps for highlighting, annotating, and enhancing PDF management on Android is broader than ever. From minimalist solutions to complete suites for the office or study, the options adapt to any user profile. Take advantage of the most advanced tools to create an efficient, paperless, always-available, and protected note library, and take your productivity to a new level with just your Android phone.