Yes I know there are paid solutions out there (like PDFTron and PSPDFKit) but how come Apple hasn’t allocated more effort towards improving their own PDFKit?
Is somebody really going to buy an Android (and put up with numerous defects) because the native PDF support in iOS sucks?
In terms of comparative file formats, I like PDF. (I might be alone in that)
My only real complaint about it is that it is impossible to draw a circle in PDF. (e.g. a "circle" in a PDF file is a set of four or more Bézier curves.) It is rich in features, some of which are useful (form filling, signing, etc.) but some of which are bloat (e.g. CAD model viewing!)
A PDF viewer that supports 100% of the format would thus be quite the beast.
Where PDF falls down for me is uses other than display. I have a demo that turns a Word Document to a Jupyter Notebook and makes it look easy, but I dread any information extraction from PDF with my current toolbox.