Not only that, but Zotero are also incredibly generous with their storage offer. You can read and annotate PDFs on your iPad and have the annotations sync insta

Not only that, but Zotero are also incredibly generous with their storage offer. You can read and annotate PDFs on your iPad and have the annotations sync instantly with the desktop client. You can then import the annotations into Obsidian for post-processing and create flashcards, which you can then sync with Anki.