Calibre Companion has no reader

Would someone please explain why Calibre Companion has no reader? I wonder because it would be an awesome addition to it.

I love Calibre and use it on my computer to read my eBooks all the time. So I got spoiled using it and now when I have to use my tablet to read I have a reader which is different and doesn't do all Calibre's reader does.

Would anyone consider updating or something to make the Companion a reader also. Please...