HOW TO GET MY FACEBOOK PHONE ICON ON CHAT?

[Alex]

I have Facebook App on my Droid downloaded. But, even when I LOG OUT of Facebook on my desktop computer, it still says I'm online (with the green dot). I want the little cellphone Icon next to my name, but it never shows up. People always think I'm online and will message me on Facebook at like 5am, waking me up. How do I get rid of it? Logging out of Facebook on the computer doesn't turn it off. The only way my name doesn't show up on Facebook chat is if I turn the actual chat OFF when I'm on my desktop computer. But, I don't want my name to not be there ..I just want my phone icon to be there. What is the setting so my icon shows up? I can't figure it out.

[Angeleyes]

Log in from your phone, It will show mobile phone icon when on facebook using phone instead of using computer.