I dip in and out of Facebook during the day but I am not a Facebookaholic. I rarely use the 'chat' facility but I can't turn it off from my iPhone.
I know how to turn it off on my laptop but the iPhone won't let me. When i log on, people want to chat because they see I am online but I don't want to be.
I thought it took your settings from the desktop version - So if you are offline in the full site, you are offline in the mobile site - It seems there is no option to turn it off on the mobile version. Thats annoying.