Raif,
It is a function already built into the SMF forum software. If a mobile device is detected, the forum will open in a stripped down version. Like an all text-driven outline, with graphics stripped away to minimize data transmission. You will not see pictures in the post either. I was using this in 2010 with my old Blackberry (roller wheel and QWERTY keyboard) to keep tabs on the Forum. It was a bit of a pain, as there were big gaps between the menus a lot of scrolling was required, but served in a pinch while traveling.
If you scroll down to the bottom of the home page on your mobile, you should see some sort of link that says 'go to full version'. When I upgraded to a new Blackberry with touch screen; bigger graphic area, and faster 4G network, this is the mode I used. It then displayed like a miniature version of the forum, virtually the same as you see on your PC. The zoom and pan functions of you mobile touch screen are needed to see any detail though. This is the mode that I used 2012 to 2014. I forget what I did to make it open in that mode all the time. I have not used it since as I got rid of the Blackberry in early 2014 and switched to a simple mobile phone (without a data plan).
Here it is in the 'lightweight', stripped down mode on the Blackberry Torch.
And here it is in full mode.
Zoomed in to maximum. Usually you did not need to zoom this far to select links. Depends on how fat your fingers are...
-Doug
[add pictures. 29Aug16, Doug]