yashsingh1/xdaforums huggingface dataset:
[Nexus 4 General] rxzlmn:
I get more than 10% battery decrease over night (6 - 7 hours, drops as much as 15%), with only gmail, whatsapp, and facebook notifications (all of which are not doing alot during night time) in the background. this is a value I get from my SGS2 with all sorts of nonsense installed and multiple exchange accounts, on older HW with a smaller battery. The nexus is pretty much brand-new unmodified stock with very few apps installed, how can the standby be so bad? I know facebook is not exactly battery friendly, but that much just leaves me very worried. if I add more background stuff like exchange accounts I expect even worse.
[Nexus 4 General] DowntownJeffBrown:
4.2 was rushed i feel and is buggy as hell. 4.2.1 was even worse and 4.2 is a dream compared to 4.2.1 so when 4.2.2 comes out I'm hoping they worked the kinks out if Jelly Bean. Remember your SGS2 was running ICS which was very battery friendly. Now jellybeans main issue is it interface with data its wacky and unstable so in just dying for the upcoming update.

You said you were stock your best bet is to flash a custom kernel. I had horrible battery on stock and now have more than doubled my battery life.

Sent from my Nexus 4 using Xparent Blue Tapatalk 2
[Nexus 4 General] floepie:
I get on average with stock everything about 24 hours with about 5 hours of on-screen time, a few short calls and 100% wifi on-time. I'm pretty happy with the battery on this thing. It's a Rev 11 with Decemeber production date.
[Nexus 4 General] spacemanvt:
wow... really?
[Nexus 4 General] wilcoholic:
I see that most of these 5+ hours screenshots aren't running any apps or making phone calls at all. Well in that case I could probably get 10 hours of screen time in airplane mode and just watching a picture for 10 hours straight.

Thats not how people use their phones in real life. they make phone calls, browse the web, use apps, game and text. I call this cheating
[Nexus 4 General] floepie:
It's just data, man. Chill. This isn't a contest. I report 5+ hours screen time with a few calls (read: 10 minutes), no airplane mode, 100% wifi, and 24 hours usage on stock everything.
[Nexus 4 General] kyokeun1234:
OK I feel very happy now. I'm on stock ROM, stock kernel, rooted, and busyboxed

I used to end the day with 30~40% with screen on time of 1 and a half hour with light usage on 3G (Not a lot of 3G either) and somewhat moderate usage on Wi-Fi, which was poor.

Disabled location access and Google Now and GPS will be enabled whenever I enter Maps (Tasker), so I'm not losing much at all.

After disabling these, my battery has improved dramatically. Now I end the day with 50% with screen on time of 2 hours with somewhat moderate usage on both 3G and WiFi. I also played some games (Angry Birds, Ruzzle, etc). If I were to keep using the device, I could've easily used another day. Would love to show the screenshot, but forgot to take it before charge.
[Nexus 4 General] DowntownJeffBrown:
I use my phone to make about 10 calls a day probably about 35 min to 1 hour a day on average. No batteries are created equal. As far as apps what do you think im doing while my screen is on? Lol Apps and browsing :rolleyes:

This all on mobile data I never use WiFi on my N4.

Sent from my Nexus 4 using Xparent Blue Tapatalk 2
[Nexus 4 General] SkyBeam2048:
Is it some kind of contest?

In fact everybody has its own usage scenario and this is entirely OK. I am using my phone mainly for text messaging, occasionally for navigation and less than 30 minutes a day for phone calls. Due to my usage pattern i keep WiFi and Bluetooth on all day but not using 3G since I don't need fast data service for text messaging when on the go. With my current setup I recharge my Nexus 4 every second or third day which is fine for me. However also my colleague at work also calls it "cheating" and tells me it's not how a smartphone is supposed to be used.

I tend to agree partially since many people nowadays watch movies on the go, listen to music all the time and surf the web continuously. ON the other hand I personally just prefer to watch videos on big screen, prefer a real keyboard and listen to music on my speakers.

Nowadays smartphones power consumption is defined mainly by screen and CPU/GPU. While you can't do much to reduce the power consumption of the screen while on (except reducing brightness or chosing a model with different screen size/technology) the CPU/GPU power consumption fluctuates a lot depending on the usage. Even modern quad core processors are very power-saving in idle but the difference from idle to full load in terms of power consumption grows continuously. So when put on load these devices easily take 10 times more power than on idle. To minimize this impact one can reduce clock rates, use less cores or reduce voltage. Although when the screen is on still the biggest consumer is likely the screen and here you can't do much. So even if you tune the CPU to low consumption under load situation you might achieve 20% lower CPU power consumption but the complete device power consumption is perhaps reduced less than 5%.

So in general the battery size defines the screen on time. And in extreme load situations (games?) CPU load might become a significant factor as well. Especially on devices like the Nexus 4 with four cores.

The bottom line is that you can of course tune a smartphone to last 7 days in standby. But in terms of screen-on-times there is not much to tune. Moreover you are always impacting the phone functionality or comfort when trying to save power. So of course manually turning on WiFi/Bluetooth/GPS only when needed might be an option. But honestly for most of us it's just not comfortable having to deal with these things just to make the device survive a day on battery in day-by-day use. So best option here is to go for a phone with better/larger battery. It's a pity however that only a few smartphone manufacturers (like Huawei with its XL series) offer larger capacity batteries on stock phones while others seem to mainly focus on ridiculous lightweight and slim phones where for most people it wouldn't matter at all whether the phone is 2mm larger for double capacity.

So no, this is not a contest. Most people seem to get around 4-6 hours screen-on-time with exceptions due to special low-load situations and excessive power tuning.
[Nexus 4 General] floepie:
According to GSAM's Nexus 4 factory ratings, CPU idle's battery hit is a factor of 3.5. At CPU max, this rating rises to 239.7. This a 69-fold rise in battery usage. Even at the CPU's lowest rated speed out of idle, the factor is 92.6. For comparison sake, having the screen on has a factor of 42.6.
[Nexus 4 General] SkyBeam2048:
Thanks for the numbers mate. I admit that I did not check the numbers. But your numbers clearly underline that the gap between idle use and full load use is huge. So of course in reviews people complain about low battery lifetime since when you first get such a powerful mobile you will of course install software and especially play games on it.

I personally don't so I would have preferred a dual- or even single-core CPU for my daily use. Now I am using kernel settings to limit maximum clock rates which helps limiting the maximum power consumption. At 700 or 800MHz the phone is sufficiently slow for all my tasks I do with it. Although if your preferred use is "gaming" then surely you want to get the full 1.5GHz or even overclock. But then of course you should expect much shorter battery life.

I just think it's not really fair to claim Nexus 4 has bad battery life while either the services/apps run are responsible for fast battery drain or the general usage pattern. The only issue is of course that a full stock phone will ramp up CPU to 1.5GHz even when browsing the settings and therefore burn quite a lot of juice.
[Nexus 4 General] DowntownJeffBrown:
This is one major reason I'm rooted and under clocked to 1134mhz

Sent from my Nexus 4 using Xparent Blue Tapatalk 2
[Nexus 4 General] androidfoshizzle:
So checking the settings is bad?

"Vanilla android >jail broken iOS>90" TV's"
[Nexus 4 General] SkyBeam2048:
Of course. In fact even touching the screen is bad in terms of battery use. I strongly advise you to leave the phone in deep sleep without touching it at all. This will delivery best battery run times. I promise!
[Nexus 4 General] sorcio91:
So guys, someone have the answer to the question:

"What's the best ROM & Kernel combination that make a good battery life and good/stock performance"?
[Nexus 4 General] DowntownJeffBrown:
For me its Franco r31 (kernel) with KillRom (ROM)

But remember every phone is different and the kernel us really what gives you the battery life a ROM can help but 98% of the battery is kernel related. So your best bet is just test test test and also remember kernels take a few battery cycles to settle in to the battery life.

Sent from my Nexus 4 using Xparent Blue Tapatalk 2
[Nexus 4 General] sorcio91:
And for the battery taken by the screen what should we do?For example if we want automatic-brightness...a filter like "screen adjuster" that reduce the overall brightness do you think that can help?
[Nexus 4 General] YetiLanguste:
Guys, yesterday I received my smartphone, so I am new in the topic battery.

Can you tell me, if there is scope to improve run-time by closing some services?

Can you tell me how to disable 3g? I want to check, wether 2g is sufficient.
[Nexus 4 General] dirtyhamster73:
Go in to settings, wireless and networks, and click on "more", go to mobile networks and check off " use only 2g".
[Nexus 4 General] DowntownJeffBrown:
The screen will take the majority of your battery always but the dimmer your screen the less battery it uses. I don't like auto brightness much ill post a screen shot of where i set my brightness slider. An app like screen adjuster should work to save more battery

Sent from my Nexus 4 using Xparent Blue Tapatalk 2
[Nexus 4 General] deepsunzhine:
Guys we bought a phone with a beutiful screen, why do u dimmer ir screen...i like to use the phone the way its meant to be
[Nexus 4 General] dirtyhamster73:
If someone doesn't need the brightness up then why put it up? Just to see the pretty screen? My brightness is always down, no auto brightness either, it only goes up when I need it, then back down when I don't. I personally don't need the brightness up at all, I can see fine. It's only when I'm in direct sunlight that I need it.
[Nexus 4 General] Evil_munki:
If I'm indoors it's normally around 5-10%, 10% holds up well outdoors for me personally too.
[Nexus 4 General] SkyBeam2048:
I am looking for similar thing. Is there any possibility to modify the brightness auto-adjusment algorithm? Actually I would love to keep auto-brightness on but the overall brightness looks too bright for my eyes. Not sure why developers tend to think that auto-brightness does have to be fully automatic and not individual. What I am looking for is some brightness slider which works in auto-brightness mode. So when I slide it down the overall brightness shall be lower, but still brightness should auto-increase in direct sunlight. Mainly for "indoor" use I find the screen to be a bit too bright (unnecessarily bright).
[Nexus 4 General] ctowne:
So basically you want exactly what the iPhone has for auto brightness. I hate Apple, but i have to admit their auto brightness is much better/smoother than Android.
[Nexus 4 General] drpepe:
Nah I agree with thesebastian, it makes sense to shut down those services you don't need. I never have any apps syncing apart from my email.

It doesn't mean that I 'may as well go with a flip phone'; it just means we're happy to only allow non-essential apps to use up precious battery life when we load em up...
[Nexus 4 General] DowntownJeffBrown:
If it was meant to be at full brightness there wouldnt be a slider. Also why is auto brightness so dim if its not meant to be that way.

Sent from my Nexus 4 using Xparent Blue Tapatalk 2
[Nexus 4 General] bash156:
Just thought I'd post my results best screen on time for me this is with everything on auto and syncd including Google now etc

Running rasbean ROM with 47b trinity kernel
[Nexus 4 General] BarryH_GEG:
Here's a casual observation. No matter what anyone's individual results are a device that's only been out for a few months and sold 500+/-K units probably has a battery issue if it takes 216 pages in a thread to discuss whether it does or not.
[Nexus 4 General] drpepe:
If that's the case, every android phone I've owned has a battery 'issue'! :p
[Nexus 4 General] DowntownJeffBrown:
Ummm OK its a battery thread. Not a fix this f'ed up battery thread. All the devices have them and they all have lots of pages. Lol

Sent from my Nexus 4 using Xparent Blue Tapatalk 2
[Nexus 4 General] :
AW: The great battery impression thread

In case you want a smartphone with really good battery you always have to go with the Note II. But for me the Nexus works fine. With the CPU underclocked at 800 MHz and screen dimmed, it is still a great device with acceptable battery life.
[Nexus 4 General] dirtyhamster73:
Right, "that you don't need". But I use those services, I want those services, and if I have to shut them down in order to conserve "precious battery life" then what's the sense? "I" might as well go with a flip.

But I get what you're saying. My comment was more of a sarcastic "funny".
[Nexus 4 General] davidsteele1975:
I'm finding that the Nexus 4 chews battery when travelling and location services / Google Now is on, relatively more than other devices. When I have a decent WiFi connection and I'm not travelling, it's a little heavier compared to some competitors, but not so outrageous. Like DirtyHamster, I want to use certain features and I can see a day from the device... I'm confident it'll improve without having to sit down and tinker.

What's hard for me is how when idle, there's a distinctive drain. Dumb phones don't have this issue, some Android devices don't either. I'm patient enough...
[Nexus 4 General] emailrob:
I used the nexus for a 2 hour drive. With the car charger plugged in and screen on all the time, it lost battery. Over the course of 2 hours, it went from about 50% down to 30%. Running Franco r34 and Cyanogen nightlies.

So technically if I kept going it would have died on me? I forgot to take a battery snapshot unfortunately. But somethings gottabe wrong. Google now, and keyboard sounds are off. Obviously location services were on

But I've been charging today, and pm8921_eoc is at the top of the kernel wakelocks. Any ideas what's causing this? In the internal battery meter, Androis OS is taking 50% of the battery which is unusual

In related news, my data speeds have been horrendous (on straight talk). Tried rebooting and no improvement.
[Nexus 4 General] ctowne:
Was your charger the proper V/I rating? And maybe ST is throttling you for lots of usage?
[Nexus 4 General] emailrob:
yeah I think so. I'll have to try another one to double check. I've not used anything near any elusive 'cap'

I might try going back to r31 but I had data drops with it before iirc.
[Nexus 4 General] ctowne:
Just make sure it has the same output as the charger that came with the N4 and you should be fine. I'm on r31 with no data problems and ridiculously good battery life
[Nexus 4 General] SkyBeam2048:
If this is what apple has; then yes I want to have what apple has!

I wouldn't say I hate Apple. I even had an iPhone for several years. However protected myself from vendor lock-in by not spending money in app store and jailbreaking (and no, did not crack apps but just jailbroken to get the freedom to do whatever I like and install many system hacks from cydia). Then decided not to go down the road of jailbreaking and waiting for jailbreaks every couple of monts with the risk of losing everything. So I headed for Android.

But I have to admit that Apple of course introduced many features and kicked the butts of lazy manufacturers to be more innovative. Some examples like touchscreen phones, touch-optimized UI, simplification of configuration, retina screens are definitely leading towards the future of mobile computing. However these technologies are not new. Tablets existed long before the iPad but Apple is able to create a hype so anyone wants to have it suddenly. Still waiting for Laptop manufacturers to stop building in crappy screens with 1366x768 pixels. Hey, our damn Nexus 4 now has almost the same resolution and there are Full-HD mobiles just waiting at the door. So please give me my 24-inch 4K screen NOW! Apple seems to be the only manufacturer being able to make such steps. They invent a nice name like "retina" for something people in PC area have been waiting for since decades and suddenly there is a marked for it.

So yes, I am even frequently thinking about buying some Apple products; but Apple is kind of all-or-nothing. Mixing/combining is not always a good idea. I want to have a "retina" screen (4K resolution) on my desk and still being able to use it with native Linux, Windows or whatever OS I prefer.

I am also hoping for Apple to be the first on some other "innovations". Just to wake up other manufacturers. For example I am looking for a phone with a secondary e-paper display. Yes in fact something similar has been announced recently by Chinese manufacturer. But this phone has a full-size e-paper screen on back. What I am looking for is a small e-paper screen just sufficient to store 2-3 lines of text and some icons. In fact just to replace the rirdiculous notification light. Don't get me wrong, a notification light is much better than nothing (my GT P1000 had none and I often switched on the full LCD to see whether I missed something) but an e-paper display would not consume any battery expect on occasional updates. Perhaps consumes even less power than the notification light. It would allow dynamic icons and text so I would not even have to turn on the screen in many cases. So why not integrate such a small e-paper display at the bottom of our N4 in place of the notification light? Hopefully apple is doing it once and we will see hundreds of phones doing the same.

So perhaps there is an Apple-patent on the auto-brightness adjustment algorithm. But likely it's just apple being the only one able to imagine that even in auto-brightness mode not everybody would love the same (relative) light density coming from the screen.
[Nexus 4 General] dirtyhamster73:
Are you using "light flow"? I think the "pm8921" is that. I have it as well. The reason I think it has something to do with light flow, or the default led, is at the bottom of the screen shot it shows something for "pm8". Could be the stock led light though.

".
[Nexus 4 General] DowntownJeffBrown:
Pm8921_eoc is from when your phone is charging. So just ignore that one cause your phone is always awake while charging.

Sent from my Nexus 4 using Xparent Blue Tapatalk 2
[Nexus 4 General] dirtyhamster73:
What if it wasn't charging at all? I'm getting them during the day, not while charging. Or does it not matter?
[Nexus 4 General] ctowne:
Wowsers! I don't "hate" Apple i just don't like how they operate and how their hardware is so overpriced. iOS is too simple for me, there isn't enough customization. I do like the auto brightness though.

That e-ink idea would be pretty cool. Even a phone with only an e-ink display would be awesome because it would last for so long. Yea you probably couldn't play games on it, but big deal.
[Nexus 4 General] barondebxl:
I had the iphone 5 a few weeks ago and I can tell you that the auto brightness on it was f***Ed up. It wasn't working properly and there was a fix, like getting in a dark room then turn the light on or some crap like that. But when it works, yes the auto brightness works pretty good. But I think it works flawlessly on the N4 as well.
[Nexus 4 General] DowntownJeffBrown:
Hmmm strange check this out dirty straight from a kernel dev.

http://xdaforums.com/showthread.php?p=36736462

Sent from my Nexus 4 using Xparent Blue Tapatalk 2
[Nexus 4 General] ctowne:
I had an iPhone 4 for a couple months last year. I never had a problem with the auto brightness. The N4 auto brightness is too bright in the dark.
[Nexus 4 General] dirtyhamster73:
That's the weirdest thing! My phone wasn't on the charger during the day at all. Other weird thing is that I've never seen this "pm8" until today. Weird.
[Nexus 4 General] DowntownJeffBrown:
That's just crazy :eek:

Sent from my Nexus 4 using Xparent Blue Tapatalk 2
[Nexus 4 General] dirtyhamster73:
Only thing that's different is that I installed light flow on the new rma. Hence why I thought it was light flow since at the bottom of the settings for it it mentions "pm8xxx". Oh well. I'm not going to worry about it. Only mentioned it because the other poster did and it made me remember I saw that pm8 for the first time today.
[Nexus 4 General] DowntownJeffBrown:
Yea I saw your screen pick what a coincidence Lol.

Sent from my Nexus 4 using Xparent Blue Tapatalk 2
[Nexus 4 General] beegbear:
anyone else notice a vertical line drop in the battery meter when using photosphere? it seems to take A LOT of battery..literally a vertical line down
[Nexus 4 General] SkyBeam2048:
I think an e-ink mobile already exists. Unfortunately I think it's a bad compromise for a cell phone. The reason is that phones nowadays are often used to play multimedia content (video). And here e-ink sucks. It's slow on updating and takes a lot of power on continuous updates. I read about an e-ink display which is able to play video, but power consumption is potentially higher than on backlight illuminated LCD. Moreover colors are some specific type of issue...

That's why I think e-ink would be perfect for some additional status screen with mostly static content.

Pixel Qi has some (3qi?) screens which are hybrid screens. Indoors they use backlight illumination and the screen looks like an LCD and outdoors it switches to reflective mode acting like an e-ink screen with low power consumption and no backlight illumination (however monochrome in reflective/e-ink mode). Such a screen would be nice readable in direct sunlight but playing movies while sitting in the backyard is probably not as much fun as on colorful LCD/OLED.
[Nexus 4 General] undercover:
Oki doki. Time to come out in the open :)

Prelude. I was hard pressed to get 4h screen on time in 10-12h off charger. Then i screwed something up (irrelevant :p) and had to reflash stock images. So I just unzipped them, chucked fastboot + dll's in there for ease of use, and ran flash-all.bat. Yeah yeah, I could have done it manually, but since i know how, i didn't bother.

Now my next findings are sure to attract so flaming from more experienced users that will say "it's placebo", "it doesn't work like that" etc. While I don't have screenies to confirm pre flash stats, i have gathered a few post flash stats. Here we go.

Some cycles are misssing, since i either accidently deleted screenies or forgot to take them. But that should give you a general idea. WiFi used mainly, apart from last cycle, where 12 were on data only and the rest was while connected to wifi and reading a book in fbreader.

+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

And this is ROM/KERNEL i used before and after flashing images.

So for me it's fairly conclusive, reflashing stock images has GREATLY improved my battery life. I had a few chats and we came to a conclusion that it is possible that at the factory device has simply not been flashed "properly", mass flashing differs from your usual .img flashing normally.

What you think...Well, it's up to you for decide. I know someone else who's done the same, and while his improvement is not as drastic as mine, it is still an improvement.
[Nexus 4 General] ctowne:
Gotcha :thumbup: