I have the Galaxy S5 with a 2250 mA battery (I think it is)... bigger than most anyway.
My wife uses her S5 as a telephone only. It sits idle for days on end, about 12-14 days sometimes. With a few conversations here and there.
My S5 gets used differently almost everyday. Even so, on the heaviest days of use, I can easily get 10-12 hours of use and still be at 40% or close to it.
Typically it goes about 2 days per charge.
I just installed Qi wireless chargers in both of them, why bother with a spare battery?
If you think you are going out on a long outing, make sure the phone sleeps on the Qi pad before you leave...
I just plunk it on the pad at night, it wakes me up with 100% every morning..........
I have an alarm set for 40% "low battery" but I very seldom ever hear that Low Battery warning.
No two of us will have the same battery life experience with the same model phones....
Fer instance, this is a picture of my wife's battery life. Her's not mine....
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