It would be nice to have a mobile version of avast forum, it would be much more easy for mobile users. I hope that we will have a mobile version soon 8)
Is this what you are looking for http://forum.avast.com/index.php?board=37.0 ???
As far as taking the forum with you just log-in from wherever you are.
There is one or a workaround, it is called WAP2 and there is a link at the bottom of every page (see attacked) and that points at http://forum.avast.com/index.php?wap2, you could bookmark that in your phone browser.
It isn’t great (mostly text based) but easier than the full blown big screen version of the forums.
It isn’t the best alternative, but thx it is something 
Yes, not great but a better alternative than the main forum.