6 Best Apps for Annotating PDFs

PDFs, known for their reliability and universal format, have long been the go-to choice for distributing educational materials, research papers, and various other documents. However, the static nature of PDFs often limits the level of interaction one can have with the content. Hence the importance of PDF annotating apps. These are tools that will help enhance the way you interact with your PDFs from highlighting text to adding notes and comments, these apps are just amazing.

Apps for Annotating PDFs

Here are some of our top recommendations for best PDF annotating apps for teachers and students:

1. Adobe Acrobat Reader

Adobe Acrobat Reader is definitely one of my favourite PDF annotating apps in this list. It has helped me a lot with my readings especially during my graduate studies. Let’s first talk about the viewing features: Adobe Acrobat Reader provides you with an optimal reading experience through the liquid Mode and dark mode. You can choose whether to read in a single page or continuous scroll mode and with a single click you can print your PDFs.

As for the annotation features, Adobe Acrobat Reader enables you to add notes, comments, highlights, and sticky notes to your PDFs. You can even write or draw on them. And if you are subscribed, you also have the added features of editing text and images directly in your PDFs, fixing typos, add or delete images. Additionally, you can fill in PDF forms and add your e-signature using your finger or stylus.

Adobe Acrobat Reader also offers a number of interesting collaborative features. For instance, you can share PDFs with your colleagues or collaborators to comment on and you can collect these comments in a single file online. When you activate notifications you will be notified whenever your collaborators added their feedback.

Compatibility: iPhone/iPad and Android / Price: Free, offers in-app purchases / Age: 4+

2. Foxit PDF Editor

Foxit PDF Editor is another excellent viewing and annotating PDF app. Some of the key annotation features Foxit app offers include the ability to edit your PDFs the way you want. For instance, you can add audios, videos, and hyperlinks to PDFs.

You can also add or delete text and images, edit document properties, optimize PDF documents, reorganize PDF pages, fill out and save forms, add handwritten signatures to PDFs, add e-signatures to PDFs, and many more. The collaborative features it provides include: add annotations and stamps to shared PDFs, share PDF files and screenshots from inside the app, and more. Other interesting features include:

Create blank PDFs from scratch or from Microsoft Office or HTML files, scan and convert paper documents to PDFs, combine PDFs to create a new PDF, convert PDFs to Microsoft Office, and many more. You can also use the app to protect your PDFs with a password.

Compatibility: iPhone/iPad and Android / Price: Free, offers in-app purchases / Age: 4+

3. Notability

Notability is an excellent note-taking and PDF annotation app which I have been using for a number of years now. Notability lets you easily import PDFs and documents and annotate them the way you like. You can also use the app’s document scanner to create searchable multi-page PDFs to share with others.

Other important features provided by Notability include: annotate with freehand ink, drawing, and text; add photos, GIFs, and web pages; mark up imported textbooks, lecture slides, images, class assignments, and more; audio record your notes; work with two notes side-by-side; create outlines, interactive checklists, and text boxes; publish your notes in the Notability gallery and many more.

Compatibility: iPhone/iPad/ Mac / Price: Free, offers in-app purchases / Age: 4+

4. PDF Expert

Another popular PDF editor and viewer app. PDF Expert lets you add various forms of annotations to your PDFs. You can highlight, underline, and strikethrough. You can also insert pre-designed stamps (e.g., approved, not approved, confidential etc.); use sticky notes to add comments or use drawing tools to draw on your documents; fill out PDF forms with interactive fields such as text fields, checkboxes and radio buttons; sign documents; protect your PDFs with passwords, edit or modify existing text; and more.

Compatibility: iPhone/iPad and Android / Price: Free, offers in-app purchases / Age: 4+

5. iAnnotate 4

Use iAnnotate 4 to annotate your PDFs using a pen, highlighter, typewriter, stamp, straight-line, note, underline, strikeout, photo, voice recording, arrow, rectangle, circle, and date stamp tools.

iAnnotate saves your marks up in the PDF enabling you to access them on any PDF reader you use. Other interesting features provided by this app include:

Compatibility: iPhone/iPad and Android / Price: $9.99 / Age: 4+

6. PDFelement

PDFelement is both a PDF editor and scanner that enables you to read, create, edit, annotate, and convert PDFs. PDFelement also supports text recognition allowing you to extract text and images from scannable objects.

Other interesting features provided by PDFelement include: change font size and colour of original text, edit text and images, remove cluttered backgrounds, add notes and comments, draw shapes, supports handwritten signatures and imported image signatures, fill and sign forms, convert to of from different file formats (e.g., word, excel, PPT, pages, PNG, JPEG, TIFF, GIF), combine files into a single PDF, and many more.

Compatibility: iPhone/iPad and Android / Price: Free, offers in-app purchases / Age: 4+

Apps for Annotating PDFs

Final thoughts

I hope you have found this collection of PDF annotating apps helpful. From Adobe’s comprehensive features to Notability’s specialized note-taking capabilities, these apps cater to a diverse range of needs. Give them a try and share with us your feedback.