Hi Judi,
Not really a much more advanced workaround than what you're already doing, but people can log onto the Attendee Hub website from mobile devices as well (from their browser, different than downloading the app!) and join the live chat from there.
Hopefully the Mobile App will eventually have that feature!
Another workaround would be to use a third party like PollEverywhere that everybody regardless of format can access at the same url.
Cheers,
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Béline Falzon
Event Planner
Stanford University
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