Perusall

Perusall is a social web annotation tool intended for use by students at schools and universities.

[1] It allows users to annotate the margins of a text in a virtual group setting that is similar to social media—with upvoting, emojis, chat functionality, and notification.

[4] As of 2024, Perusall states more than 5 million students have used the tool at over 5,000 educational institutions in 112 countries.

"[1] Perusall integrates with learning management systems such as Canvas and Blackboard to aid with collaborative annotation.

[2] The tool supports annotation of a range of media including text, images, equations, videos, PDFs and snapshots of webpages.