POLAR - Easily manage your reading including PDFs, web content, and notes.
I actually joined Indie Hackers after I created Polar and never really posted here about it directly.
I created it for myself actually as a tool to manage all my reading.
Everything goes into Polar. Anything I want to read that's meaningful and that I want to maintain long term.
Mostly technical books and important documents.
Recently I've been doing a ton of reading on startup growth and customer acquisition.
Polar keeps track of what I read by using "Pagemarks" which I update as I'm reading the document.
Then I can create annotations and comments on the important sections and sync them to Anki.
I'm still working on the marketing material and the landing page and I definitely need to do a better job of making the pitch a bit easier to understand.
... but I think this might be right up your alley if you read a lot of important documents like I do.