[liampronan]

I'm always looking to better my flow for PDF reading so really appreciate this question.

I have settled with Notability due to its nice iPad app where I use my Apple Pencil to annotate - the annotated PDF syncs to iCloud so it's available on Apple products (don't think it supports Android/Linux so maybe not cross-platform but something I'd recommend checking out if you can live with that limitation). If it's a book I'm using to learn something (usually tech), I then transfer notes to Bear in outline format (using the Notability mac app to read notes) and sometimes Anki for flashcards. One downside is that Notability doesn't support ePub so I either convert those or read on Kindle.

I tried OneNote recently but the iPad app seems unable to handle larger PDFs like textbooks which is a major bummer and surprising to me.