I am completely new to Android, and want to just put a few things out there itemized so people can see what I experienced and what I did and did not do with my phone for battery issues etc.
My phone when I got it was getting horrible life. I would use it like 2 hours or sometimes 3... EVEN when not using it the thing seemed to die within that short time span.
This is why.
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1. The ONLY things that really added to my battery ... and SERIOUSLY ONLY THINGS -----
a. Disable GPS/Wifi/Bluetooth when not being used
(There is a power control widget you can use on the front screen even to make it convenient.) This is not any 'above and beyond' and is a basic think you really would do with any phone more radios = more battery.
b. Disable 4G when not needed. The phone is 4G yes, but you should only use it when you need the speed increase for streaming media or downloads etc. In the mean time 3g is way more than sufficient. Also if you are outside of a 4G area it is going to rape your battery searching.
c. DIM BACK LIGHT TO MIDDLE SETTING (Also in the widget, it is 3 levels of brightness the display is huge and I actually like the image unless needed in bright daylight to be at the middle setting) However this was not a major difference.
d. TURN OFF AUTO SYNC - BUT NOT BACKGROUND DATA, The auto sync was in the list of processes that used the most cpu/battery. Mainly Facebook.
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2. Processes and comsumption of battery/performance etc (Task Killers) -----
- Without ATK I have 21 processes open but are not active and learned from the forums that the kernal works differently from my WM experience and it is not eating up the system memory and processes will be prioritized as needed without killing everything (As I understand).
Result - I have had my phone running with no task killing and see no difference in speed, battery life or performance. Infact I had used another 3rd party app that physically displayed those processes were 'up but inactive' and not using any resources.
I do however believe but not sure but 3rd party apps could be poorly programmed it causing issues or constantly eating cpu without quitting.
Anything outside of this may gain you battery life but is not necessary. Custom roms are not the overall solution if you want better battery life. They may provide better battery life yet the user should be into it more for what they offer for abilities and the mods.
----- SO SIMPLE. To sum it up. -----
Turn off Radios bt/wifi/gps/4g (Don't leave them searching for items that are not present)
Disable Auto Sync (Items like Facebook that could potentially eat up data and cost a LOT of battery fast and the #1 killer of life)
Change Screen Brightness (Least of the concern but my particular screen was pleasing in normal lighting at the middle brightness setting)
Im getting about 8.5 hours of hard internet usage, texting, some video streaming etc. I believe that is very respectable for a phone of this power and caliber without freaking out, over complicating and thinking your amazing phone is not out of the box capable expected performance.
Hopefully some people wanted to be clear on that and I had some correct answers in there if not please correct me but my phone is running great in the states I just described.
I just drove 700 miles and I'm a bit tired sorry if I had any repetition or anything too bad in how I wrote this lol