I prefer my iPhone to any android phone but google music is a lot better than Apple Music. At least I can use google music without fear of it messing up my music library. Apple Music I dare not even activate.Nexus 6P
And Google Play Music is significantly more streamlined and stable than Apple Music.
Google maps is without a doubt better than Apple maps.
I think I would agree that battery life is far superior on the 6S +. However if were getting 5 hours screen time on an android phone considering it would have a higher resolution than the 6 plus I'd be more than happy. The only issues I have is poor standby battery life and those rouge battery days when your battery just rapidly drains for no apparent reason.
I think iOS excels in fluidity and overall polish, integration between devices, ecosystem as a whole and the software is a better fit to the hard ware. That's what keeps me on iOS.