I just recently remodified an install of awstats to detect ios and iphone, and while I was at it, I reapplied my changes to detect our xymon server as well.
Following the instructions here: http://cornempire.net/2009/08/31/adding-a-robot-to-awstats/ and here: http://wiki.cornempire.net/awstats/awstatsrobots still work. I just made a small tweak to match our new version of xymon, and also to make the detection more broad, which should future proof it a bit: http://wiki.cornempire.net/awstats/awstatsrobots#updatejan_21_2014
As a side note, if you are trying to detect ios for iPhones and iPads, this tutorial is useful: http://serverfault.com/questions/248692/analyze-http-logs-looking-for-ios except for one thing.
I received an error about a mismatch in the number of entries in the @OSSearchIDOrder and %OSHashID. This was because more recent versions of awstats includes basic ios detection, and because the footprint of the new code has the same ios label as the stock code, it would throw this error. Commenting out the built in ios detection did the trick for me. I may try to expand upon the ios section a bit and try to detect version numbers in a future version. I may also create a patch that breaks out iOS and Android devices to a new family called tablets, or mobile devices….maybe.