In the container field display settings on your filemaker layout, you need to set it to be an interactive container for the Insert PDF menu item to not be greyed out.
iOS I believe takes care of this for you regardless of settings due to the differences between FMGo and FMPro
For some reason when I first tried making it interactive it didn't work. So I deleted the container completely and inserted a new container and that worked.
However, although it works well in Windows and Mac I can't seem to get it to work properly in FMGO. The PDF does show up and I can move to various parts of the PDF but I can't copy a section. Is there something I'm missing or haven't done?
I tested a container with “Interactive” and “Reduce or Enlarge Image to Fit” using FM Go 15 on iPhone and iPad. Touching the container with a pdf, causes a popup with “Actions”. Choosing the “View” Action, allows selecting and copying images and text from the pdf.
Furthermore, if you have in the iOS device a pdf reader, editor, you may export / open the pdf in the reader, perform copying or editing and return to FM Go.
There are a myriad of pdf apps in the App Store, some are free, and others …
Sometimes the issue is the PDF file rather than FileMaker.
A PDF can show what looks like text but is really an "image" of the text. In such cases, you cannot copy and paste text from the PDF no matter what application you've used to open the PDF as there is no text that you can copy.
A PDF file can also be “locked” to prevent any interaction such as copying.
Also, if the PDF contains an image of text, rather than text, copying may not be possible.