The S6 was very hit or miss for most people regarding battery life, in my case I get nearly 6 hours of screen on time with my S6 with the majority being WiFi usage. There's plenty of people on the opposite end of the spectrum though, barely making it through half the day.
The Note 5 also seems to present a wide range of battery life figures, some people seem to be getting exceptional battery life while others are struggling. The software is the leading culprit in this as wake locks and other issues are leading to dismal battery life for some.
One of the benefits of Apples locked down nature is the lack of software issues leading to excessive battery drain. There is few things you can adjust on an iPhone besides location and sync settings that can affect battery life, the rest is pretty much taken care of by Apple itself. This combined with Apples exceptional optimization leads to the amazing battery life found on the 6+ yet most tech sites that conduct standardized tests don't accurately account for the real world battery life experienced by the real users.
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