I've had some bad experiences with Tapatalk in the past unfortunately, as they've had security problems a couple of years ago - which lead to data leaks (not affecting us, but other sites). As the site has a mobile template (it'll re-size the forums and work well on phones) then I'd rather avoid having a 3rd party plugin on the site. I can see why it's easier for the end user, but it can introduce some major headaches from an admin side of things.