I don't recall, but did you ever say what phone you would be coming from if you change to a Note 5 or an iPhone 6S?
FYI, you said that you use your phone all day, but you are also reading textbooks, so you are likely a student. I expect that your phone would go through periods on standby while you were in class.
I just wanted to show you what my battery life was today where my phone was used very little-- about 50 text messages, browsing Facebook for a short period of time, half a dozen emails, and a bunch of CNN and BBC notifications popping up. I had too much work to do, so I couldn't use my phone much.
My phone, only used for 1.5 hours, dropped to 88% over the course of 12 hours.
If I hadn't touched my HTC One M8 at all, not even turned the screen on, at this time I would probably have 80% or less battery life.
The battery life is fantastic.
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