i use an adaptivecard with input.choiseset and i used markdown formatting to put a link inside the "title" of the choices.
on desktop client everything works, the title is shown as a link, but on my iphone 7 (newest version of webex app) the markdown formatted link got not converted to a clickable link, it shows it as text.
i got this reply from dev support:
Markdown links aren't officially supported in cards. Supported markdown within the adaptive card framework are listed on https://docs.microsoft.com/en-us/adaptive-cards/authoring-cards/text-features. Guessing the desktop client that you're using is the Windows one because it's the only one that hasn't been updated to use native rendering and instead is still doing HTML rendering which allows the markdown to work but it was never officially supported.
Please add this feature to mobile clients if possible.