Same here. On the home computer, I've been using Firefox for most purposes (including browsing yacf), for a few years but recently I've been getting messages warning me that it no longer supports my OS (OS X 10.5.8) and occasionally behaves in a slightly flaky fashion so I'm probably going to have to change one or the other.
To answer the OP, I mostly use Tapatalk so I checked "other", but I guess that as an iPhone app, it's technically some kind of shell based on Safari, right?
I've just realised that none of the devices I use regularly to access the web even have IE installed. And I've never once missed it. (Admittedly, all the devices I use regularly are Steveware, so maybe it's not really that surprising.)
d.