Not enough information for anyone to even guess at answering your question. Please read my signature link on making a "Quality Post". Post back to this same thread and we'll try to answer your question.
I typed this after reading your responce before I noticed only the last sentence of my post showed up.
What a idiot/bonehead move on my part.
"Seriously you can not tell that I'm asking if iPhone/ipad OS8 messenger is available on an OS X devices.
I can't believe this did not show up in a search."
Is the OS phone pad messenger available/ or at least a work around
OK, now that we know you're running the latest version of OS X (Yosemite), the answer is yes for both your MBA and the iMac. Check out this Apple KB article which shows you how and which clients can be used. LINK
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