I do occasionally, but only ever to lurk. I'm signed in on it, but I never post.
My screen is just a little bit too awkward. Have to zoom in some considerable bit, and the zoom function doesn't always work.
And if I want to click a link, like choosing a topic from the Boards, then I have to really really zoom in, otherwise I'll end up just picking almost anything with my thumb.
I only ever use it if I am at college though. If I've got a bit of a break, or I'm waiting around outside for a class to begin then I might have a little look-see.
Otherwise I'm at home and have my computer, or I'm on the move, and I'm a hazard if I'm walking and looking at my phone.