See Brion Vibber’s post — we need more testing on the mobile gateway for English Wikipedia. Brion’s slipped in some JavaScript which intermittently pops up a link if it detects an iPhone/iPod Touch or Android device. There’s also gateways for the German and Wikipedias.
(I must say, I really like the mobile skin — I was running the “classic” skin on Wikipedia for ages, but it was too ill-maintained and I had various wacky user JavaScript that didn’t work well on anything but Monobook. The mobile skin doesn’t allow editing as yet, but is great for viewing.)
Dude, I use an iphone app to view the wikipedia a lot. It works very will, IMHO. It’s called “Wikiamo”.