Issue displaying PDF figures created with R on iOS devices
embedFonts
by default doesn't embed the standard PDF font set, and therefore doesn't actually make any significant changes to your example PDF. Try instead
embedFonts("figures/ios-example.pdf",
options="-dSubsetFonts=true -dEmbedAllFonts=true")
and if that doesn't work, tack "-dPDFSETTINGS=/printer
" on there too.
[EDIT August 2020: With current versions of R, another thing to try is switching from the pdf
device to the cairo_pdf
device. cairo_pdf
uses a more sophisticated library for PDF generation and, among other things, it embeds fonts itself.]
For what it's worth, though, your example is displayed correctly on the only iOS device I have to hand (iPad, OS version 4.2.1).
You could also try telling R not to use the Dingbats font to draw points: pdf(..., useDingbats = F)