PDFill might be a bit more popular than MarginNote. We know about 1 link to it since March 2021 and only 1 link to MarginNote. We are tracking product recommendations and mentions on various public social media platforms and blogs. They can help you identify which product is more popular and what people think of it.
The Strange New Worlds community plugin goes part way toward this approach. Apart from Obsidian, the MarginNote note taking and PDF/ePUB annotation software performs a similar function to Notation, with MN's "title link" feature. Source: over 1 year ago
Pdfill, has an excellent editor and a set of free tools - https://pdfill.com/. Source: almost 2 years ago
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