Is there an IM app or service that will allow me to enlarge the text size?

[Blayzn]

I was using the web Meebo mobile IM service, but since this last update, I can't really use it. I was able to pinch and zoom to make everything large (I'm visually impaired). But, since the update, everytime I would try to type, my keyboard would disappear, and it's VERY annoying. So, I was wondering if there was another app or web service I could use that would allow me to do the same thing, or be able to enlarge the text size in the options. Any help would be appreciated.