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Preview of Spatra

Spatra by Babyze

Turn the web into your knowledge space. Highlight, annotate and keep thoughts anchored to what you read.

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About this extension
Every day we read articles, documentation, research papers, and PDFs — but our thoughts usually end up separated from what created them. You find a great paragraph, switch to a notes app, paste a link, type something. Months later the note is still there and the reason you saved it is gone.

Spatra brings the missing layer back to the web.

Highlight a paragraph, write a note beside it, draw on a diagram, connect ideas together, and come back later without losing the original context.

BUILD YOUR KNOWLEDGE LAYER
• Attach notes directly to paragraphs, pages, and PDF documents
• Highlight text in 5 preset colors, or any custom color you pick
• Write thoughts beside the exact content that inspired them
• Draw, sketch, add arrows, boxes and text, and annotate diagrams
• Capture a selected region of the page, or paste an image straight onto it
• Link notes and documents together with [[wiki-links]]
• See how your ideas connect, as a graph, in the Spatra web dashboard
• Search across everything you have ever highlighted or written

READ AND ANNOTATE PDFs
Open PDFs in Spatra's built-in viewer: right-click a PDF link on the web and choose "Open in Spatra PDF viewer", open a file from your computer with the file picker, or drag and drop it in. Highlight text, draw on pages, add notes, and jump back to any annotation later.

Your learning materials become part of your personal knowledge system.

YOUR NOTES BELONG TO THE CONTENT, NOT THE POSITION
Websites redesign. Paragraphs move. Spatra re-finds your highlight by its content, not by a fragile scroll position.

If a passage truly disappears, your note is not deleted — it lands in "Orphans" with a snapshot of the original text, the heading it lived under, and where it came from. You never lose what you wrote.

CONNECT IDEAS ACROSS THE WEB
Link a highlight from an article to a PDF page, to another site, or to your own thoughts, using [[wiki-links]] right inside your notes.

What you read stops being a pile of separate pages and starts being a personal knowledge graph. Open the Spatra web dashboard and you can see that graph laid out visually — click any point in it to land back on the exact passage it came from. The dashboard is also where you share an annotated page with someone else.

YOUR KNOWLEDGE, YOUR DEVICE
Everything works offline and is stored locally on your device by default. No account is required to start.

Export any time to JSON, Markdown, or Anki decks, or sync two-way with your Obsidian vault. Obsidian integration requires its free Local REST API plugin, and Spatra Options walks you through connecting it.

OPTIONAL CLOUD SYNC — PAID SUBSCRIPTION
Sync across devices, open the web dashboard with its search and graph view, and share an annotated page with others through a public link. Search inside the extension itself always works offline with everything stored on the current device.

Your local data continues to work whether you subscribe or not. If a subscription ends, everything remains readable and exportable.

PRIVACY
Spatra does not collect general browsing history, use advertising trackers, or sell personal data.

Cloud Sync is off by default. When enabled, Spatra stores only the user's account information and annotations selected for synchronization: highlighted text and context, notes, drawings, and the title and URL of the annotated page. Pages that the user has not annotated are not uploaded.

Connecting Obsidian or sending feedback are separate, explicit actions initiated by the user.

Full privacy policy: https://spatra.app/privacy
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Permissions and data

Required permissions:

  • Download files and read and modify the browser’s download history
  • Access your data for all websites

Optional permissions:

  • Access your data for all websites

Data collection:

  • The developer says this extension doesn't require data collection.

Optional data collection, according to the developer:

  • Authentication information
  • Browsing activity
  • Personal communications
  • Personally identifying information
  • Technical and interaction data
  • Website content
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Version
1.0.0.3
Size
1.78 MB
Last updated
4 days ago (Aug 15, 2026)
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  • privacy
  • scholar
  • search
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