[Galaxy S 5 Android Development (Snapdragon)] xXx:
As several users posted battery drain issues lately I did some new tests over the weekend based on the latest v5.2 rom.

I dirty flashed 5.2 over the previous 5.1 installation using all available options

root.supersu=1

deodexed.rom=1

kernel=3 # Boeffla Kernel

keyboard.mod=3 # C5 Keyboard

systemui.mod=3 # White themed SystemUI

xXx.tweaks=2 # all xXx Tweaks + Qualcomm Adreno 330 Beta Drivers

xposed=2

sound.mod=2

camera.mod=1

I left the and left the device alone with screen off but WiFi, Bluetooth, GPS, NFC enabled and Boeffla Kernel on default settings. I wanted to figure the pure base rom consumption. Therefore except the stock weather widget I didn’t enable any app to do regular activities in the background. What I mean by that is checking for new Emails, Whatsapp, Facebook and you name it.

After about 25 hours (1 day) I checked for the battery level and it was on 90% left which is about 0.4% battery drain per hour. (first screenshot) This means the device would survive more than 10 days without charging.

Next I wanted to know how the battery survive with screen on. I made sure the screen doesn’t turn off and left the device alone again with dimmed screen showing the standard TouchWiz launcher screen on a brightness level where you could still read at in-house light conditions.

When the battery was down to 10% I checked again for statistics. So with 80% battery I got close to 14 hours SOT (Screen On Time)

As the display is the biggest battery drainer SOT depends very much on the screen brightness. The test values above was performed with quite low level brightness. If you run your device on quite high brightness the SOT will go down dramatically but I just wanted to show that my ROM with all available options enabled provides a very battery friendly environment.

I also did a quick test to see how much battery is used when screen is running on max brightness. I started from 100% again and drained down to 90%. In this case SOT was about 1 hour which means that the SOT would be max 10 hours with max brightness. So taking the above numbers the max SOT for low brightness is about 17.5 hours vs. 10 hours with max brightness. This means, depending on the screen brightness you choose, battery drain could be up to 75% more if you are on max brightness compared to low brightness. As you can see on the last screenshot the max brightness screen is the biggest battery drainer eating more than 90% of the juice.

Unusual Battery drain in screen off mode is almost always caused by certain app or additional services with high background activities.

If you experience unusual battery drain or you are interested how to further increase battery life I highly recommend you to head over to the thread from @v7 He is really awesome and very responsive if you need help.

http://xdaforums.com/android/general/guide-extreme-battery-life-t3095884

I followed nearly all suggestions he provides in the op for my S7 Edge and I could significantly reduce battery drain. I didn’t had any battery drain issues before but his guide helped to further reduce battery usage without compromising on daily usage. So for example I always keep data, Bluetooth, NFC, GPS etc. on when screen is off and even though I saved significant juice.