I just bought the iphone6s plus. I have two issues, flickering and battery life.

I just bought the iphone6s plus. I have two issues. One the battery life is poor. I have checked the battery usage and there seems to be a lot of background activity for messages, mail, settings, and Facebook. 2 issue is flickering.

I have restored to new and still the same issues. its extremely annoying. Anyone else have these issues? Any solutions?

thanks