Bottom line: For researchers, MarkLayer is a free annotation layer over any web source. Highlight, comment, and share with collaborators via a single link. No account, no per-seat fee, no central database holding your reading history.
Research workflows live in a tab graveyard. Articles, dataset pages, government reports, blog posts, archived news. MarkLayer adds a free annotation layer over any of them. Highlight passages, pin notes-to-self, draw arrows between connected claims, and share annotated sources with co-authors or peer reviewers via a single link. No account, no upload, no paywall.
The problem
Reference managers (Zotero, Mendeley) handle PDFs well but treat dynamic web sources as second-class. Hypothesis works for text but not for visual annotation of charts, infographics, or layouts. Most paid alternatives charge per-seat for what should be a basic web utility.
Why MarkLayer fits researchers and academics
Free with no per-seat licensing. Useful for collaborative research projects across institutions.
Anonymous. No central account tying your reading list to a profile.
Visual annotation: arrows, drawings, and pinned comments work on charts, infographics, and layouts. Not just text.
Multi-page projects bundle several sources into one shareable link for a literature review.
Open source and self-hostable. Fits institutional security requirements.
Co-authors view annotations without sign-up; replies thread on the source itself.
How it works
1. Open the source. Open the web article, dataset page, or report you want to annotate.
2. Annotate findings. Highlight key claims, pin methodology questions to specific paragraphs, and draw arrows between related figures.
3. Bundle related sources. Use multi-page projects to combine several annotated sources into one share for a literature review or argument.
4. Send to co-authors or reviewers. Share the project link via email or Slack. Recipients see all annotated sources without signing up.
5. Discuss in context. Co-authors reply to your pinned comments directly on the source. No parallel Google Doc needed.
Frequently asked questions
Is MarkLayer better than Hypothesis for researchers?
It depends on the source. Hypothesis is the standard for scholarly text annotation, with W3C-standard anchors and public groups. MarkLayer is better when sources are visual (charts, infographics, layouts) or when you need a no-sign-up share link.
Can I export my annotations for a citation manager?
Not natively. MarkLayer is built around shareable links, not file export. For citation export, pair it with Zotero or Mendeley for the citation itself and use MarkLayer for the working annotations.
Does MarkLayer work on PDFs hosted online?
MarkLayer annotates web pages. PDFs in browser viewers behave differently across platforms. For reliable PDF annotation, use a dedicated PDF tool. For HTML versions of articles, MarkLayer works directly.
Is the data I annotate private?
Annotations stay on your device until you generate a share link. There is no public feed, no profile, and no central account tying annotations to your identity.