Hyperlinks in PDF documents not working

We are creating documents in html, which we then run through an html-pdf converter to have a pdf document that is emailed as an attachment. We have a document that we want recipients to be able to respond to by email, so are using the html mailto tag to create a hyperlink within the document that recipients can then select to create a reply email with address and subject line pre-populated.

This works quite okay when tested on a PC, the link within the PDF document responds as desired within Outlook and Adobe Reader.

However, we have discovered that if the email is read on an iPhone or Samsung phone the hyperlink within the pdf does not appear to work. Any attempt to select the hyperlink simply selects the text and allows the usual copy etc. options for selected text. This appears to be the case in either the email app on the phone or even when opening the attachment in Adobe Acrobat app.

Is there a way we can have this reply email hyperlink working regardless of what platform the email is received in?

(Crossposted in Adobe, Apple and Samsung forums)