If you're interested in using a commercial product the LEADTOOLS SDK can perform this conversion for you. They have Xamarin libraries available for DocumentConversion.
The conversion also takes place on the device where the libraries are, so no internet connection is required. The libraries can ...
I think the answer is no.
A PDF file is basically a picture (or raster in GIS terminology)
To make a picture into Polygons, Lines etc you would have to put it into a GIS Software package (e.g. QGIS), make sure it's in the correct position on the Globe (Georeferencing) and then trace over the top (Digitize new features).
Also from a quick look at the ...
Machine-readable PDF files can actually be opened in the current MS Word program. You just need to open the PDF using MS Word. A pop-up warning will appear and once you've confirmed this, it will open as a Word file where you can edit the content like a .doc file and save as PDF again once done.
However, this works only to machine-readable files. Meaning, ...