Currently there isn't a mobile friendly version of the site, and this is an unfortunate omission of the site.
This is really something I should work on at some point but unfortunately SMF is not that well geared up to handle client responsive page sizes as of today (vBulletin is more modern in that regard, SMF 2.1 will have much better native support for mobile sites but that is still in beta as of today). There are also mods that can be installed over the base SMF installation but we are hesitant to try those based on some bad experiences with mods corrupting the site and resulting in a complete loss of the database in the past.