I wouldn't say IOS is free, the cost of IOS is baked into the cost of the iPhone. Android on the other hand has a distinct line between OS vendor and handset vendor and while Android AOSP is free, handset vendors do need to pay for Google services (GMS) like gmail, maps, play store etc.
Through Airplay, right? Airplay has lots of issues for me, even on a direct wired connection via latest Airport extreme router. There are a couple of websites I watch video on where it would be much better (performance and quality wide) if I could just visit them directly via a browser on appletv.