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[Q] is rooting always like this

Maybe this is due to my lack of experience, but maybe not. It seems like every time I put a new ROM on my phone it goes to hell in about a month. I'm not a technician but I can follow directions for installation, patches, etc. So far I have had 0 long term success in installing a ROM that ends up being any better than stock after 30-60 days.
For example, I've had issues with battery drain, random booting while the phone is powered off, redraw issues, serious lag, data connectivity issues, and a few other things. It seems like its always something.
The only phones I've toyed with are my old Eris and my Charge. Is this a phone issue, noob issue, or is this par for the course? If it is par I'll end up back at stock and have mediocre performance rather than have a buzz saw that ends up needing constant tweaking and maintenance.
Btw this isn't a knock on developers. I appreciate them sharing all their hard work. I just want to know if everybody else goes through this or am I holding a bag of stupid.

Just rooting does nothing more than give you superuser access. It doesn't even do anything that uses the root specifically. Different roms do different things, but nothing to use battery...mostly they take things out rather than put things in.
Best thing to do is look at BetterBatteryStats and track partial wakelocks. That will tell you what is waking up your system and if there's anything spiking it, you can deal with it. Most of what really drains battery on this phone, other than bad apps, is somewhat random, and it will affect non-rooted phones just as much as rooted.

Must be something you did, picking a good rom make a big different. In my case. I flashed tweakstock to my daughter's phone since the first day it released (with tweakstock kernel), and never, I repeat never have any issue, when tweakstock 1.4 released, this is the second time I touch her phone and up until now she hasn't have any issue. If you use eclipse rom, PBJ kernel, Imonsey kernel, you're going to have issue. They are not bad roms or kernels, but they do have bugs. This is my experience.

Yeah, I think it's you. On stock, I'll be lucky to get 12 hours usage in a low signal environment. On a custom ROM, with custom kernel, I'll make it through the day. Of course, I've had a couple of random total crashes where I had to go at it again, but I deal with it.
PROTIP: the Facebook app needs to be told to stfu constantly. I would get an app like System so you can kill it easily-it still stays in RAM and in wakelock, taking clock cycles, even if you close it by backing out. I found that this was one of the best battery savers.
Sent from my SCH-I510 using xda premium

kvswim said:
Yeah, I think it's you. On stock, I'll be lucky to get 12 hours usage in a low signal environment. On a custom ROM, with custom kernel, I'll make it through the day. Of course, I've had a couple of random total crashes where I had to go at it again, but I deal with it.
PROTIP: the Facebook app needs to be told to stfu constantly. I would get an app like System so you can kill it easily-it still stays in RAM and in wakelock, taking clock cycles, even if you close it by backing out. I found that this was one of the best battery savers.
Sent from my SCH-I510 using xda premium
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Yes, I agreed with kvswim, Facebook is a big battery drainer, I ended up using the browser for facebook, it's not as nice as the FB app, but once you get a hang of it. It's fine. I suggest if you want trouble free, ODIN pit file and original factory image, then upgrade to tweakstock with tweakstock kernel, then install Go launcher for smoothness. To save battery even more install battery saver by Antutu.(keep all default settings, don't play with it). You will see big improvement with both battery and smooth trouble free phone.

Please use the Q&A Forum for questions &
Read the Forum Rules Ref Posting
Moving to Q&A

buhohitr said:
Yes, I agreed with kvswim, Facebook is a big battery drainer, I ended up using the browser for facebook, it's not as nice as the FB app, but once you get a hang of it. It's fine. I suggest if you want trouble free, ODIN pit file and original factory image, then upgrade to tweakstock with tweakstock kernel, then install Go launcher for smoothness. To save battery even more install battery saver by Antutu.(keep all default settings, don't play with it). You will see big improvement with both battery and smooth trouble free phone.
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you really find a battery saver to be helpful. Every time i try one it ends up costing me more battery life than it saves.
As for the phone issues. Are you wiping data, cache, and dalvik before you flash? Not doing so can really muck things up. And a lot of times its just an annoying app that sucks up all ur juice, ie words with friends and facebook. I use them alot so I deal, but u can definitely tell the difference when u dont have those apps installed.

No i dont think its u...i have problems also.i jus made a post about my home/hard key...its always seems to b something after the next.but it looks like people find ways to deal and eventually conquer.also i appreciate wat the developers do.its alot of work and headaches.on top of posting and replying to many many people.its the roms that cause problems...constant tweaking and toying around...alot of times things jus need to b debugged a little it seems.but its all in the nature of what were all doing here.good luck to u
Sent from my Gummy Charged GBE 2.1 using XDA App

cnoevl21 said:
you really find a battery saver to be helpful. Every time i try one it ends up costing me more battery life than it saves.
As for the phone issues. Are you wiping data, cache, and dalvik before you flash? Not doing so can really muck things up. And a lot of times its just an annoying app that sucks up all ur juice, ie words with friends and facebook. I use them alot so I deal, but u can definitely tell the difference when u dont have those apps installed.
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Hey. how about give the "battery saver" app by Antutu a try. This is one of the kind. It does not kill processes like others. It actually readjust cpu frequency during usage and put your phone in heavy deep sleep, after installed, let it run for 2 days, you will notice at least 3-4 hrs more during usage and 10+ if you let your phone sleep. I have test this app with wifi,4g,gps on 24/7 and I still have good battery life.

I downloaded betterbatterysaver to check my stats. Now to figure out how to read the data. Any suggestions? I've searched Google and it seems to be a mystery for many. It appears that Dolphin HD is using most, but I kill the program when I'm done???? I switched to mini and froze HD to troubleshooting. I only use FB browser too. I ditched the app long time ago.
Before I flash I wipe dalvik cache, data, and then wipe it again. I follow directions closely since I can't figure my way out if something goes wrong. I'm running tweakstock's latest right now and I'm really enjoying it. Very stable and snappy. However, the battery problem is killing the experience. It drained fro. 69% to dead in 6 hours overnight! Switched from 1.1 because the phone got very laggy and the hand off between 3-4g was getting dropped and I was losing data connection.
I will try the battery saver app. Just got battery calibrated and still not any better. My need to have a phone that doesn't suck will keep me playing with this thing until I get it right. My Charge is used so much it's like my third hand.

donkason said:
I downloaded betterbatterysaver to check my stats. Now to figure out how to read the data. Any suggestions? I've searched Google and it seems to be a mystery for many. It appears that Dolphin HD is using most, but I kill the program when I'm done???? I switched to mini and froze HD to troubleshooting. I only use FB browser too. I ditched the app long time ago.
Before I flash I wipe dalvik cache, data, and then wipe it again. I follow directions closely since I can't figure my way out if something goes wrong. I'm running tweakstock's latest right now and I'm really enjoying it. Very stable and snappy. However, the battery problem is killing the experience. It drained fro. 69% to dead in 6 hours overnight! Switched from 1.1 because the phone got very laggy and the hand off between 3-4g was getting dropped and I was losing data connection.
I will try the battery saver app. Just got battery calibrated and still not any better. My need to have a phone that doesn't suck will keep me playing with this thing until I get it right. My Charge is used so much it's like my third hand.
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Did you try to disable(freeze) SDM app and also Google service? May need to backup all your apps and do a factory/data reset, If not help, possible to re ODIN factory image (see pos # 5) since you have data drop issue. Some thing is mess up in your OS.
For betterbatterystats look at wakelock and see what process used the most.

If it died overnight then something is definitely eating your battery. Are you in a low signal environment? Go to settings, about phone, then battery usage. If anything besides display is taking more than around 5-10% (can be more if you use it a lot) then that's your main problem. If your cell standby is more than 25% it's the low signal that's killing the battery.
Sent from my SCH-I510 using xda premium

Data is up and running smooth after flashing newest tweakstock. My home has a strong signal and my bedroom is sometimes 4G so I don't believe the signal was low, unless the transition between radios killed it. However, it wasn't a problem 3 weeks ago.
I did freeze SDM and noticed some improvement. Buhohitr, did you mean freeze Google services framework?
Battery usage seems to be normal for now. I am noticing Dolphin is no Singer sucking down 35% or more since I switched to Mini. It doesn't even show up on the list.
I'll see how it goes today and report back on wakelocks. If it doesn't get any Beyer ima Odin to stock and root/flash tweakstock again.
Also, the battery doesn't drain unusually fast wile in use, browsing, music, etc. But when it sits it drains at 3-4% an hour.

I would try manually calibrating your battery. It really worked for me. On average I get about 18-19 hours on one charge with medium to heavy data usage throughout the day. There is a thread in the General section.. I'll post a link in a little bit.
EDIT: Here is the link. It's a stickie but I figured I'd save you a little extra time. http://forum.xda-developers.com/showthread.php?t=1187698
Sent from my Tweaked Droid Charge using XDA App

ewh1292 said:
I would try manually calibrating your battery. It really worked for me. On average I get about 18-19 hours on one charge with medium to heavy data usage throughout the day. There is a thread in the General section.. I'll post a link in a little bit.
EDIT: Here is the link. It's a stickie but I figured I'd save you a little extra time. http://forum.xda-developers.com/showthread.php?t=1187698
Sent from my Tweaked Droid Charge using XDA App
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Wiping battery stats is a complete placebo. All the battery stats stores is the state of apps as related to various things that affect battery life (like display on time, screen brightness over time, and wakelock states). It does nothing that will actually affect your battery life one iota. It is actually cleared every time you charge your battery to 100%, so manually wiping it is completely pointless.
https://plus.google.com/u/0/105051985738280261832/posts/FV3LVtdVxPT

shrike1978 said:
Wiping battery stats is a complete placebo. All the battery stats stores is the state of apps as related to various things that affect battery life (like display on time, screen brightness over time, and wakelock states). It does nothing that will actually affect your battery life one iota. It is actually cleared every time you charge your battery to 100%, so manually wiping it is completely pointless.
https://plus.google.com/u/0/105051985738280261832/posts/FV3LVtdVxPT
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Click to collapse
I'm well aware of the post of Dianne Hackborn debunking the myth of wiping the battery stats; however, if you actually read the post on the steps to calibrating your battery, it's not just wiping your battery stats. There's actually a few more steps involved. You're right though, if you just wipe the battery stats and expect better battery life you're just wasting your time.
Sent from my Tweaked Droid Charge using XDA App

donkason said:
Data is up and running smooth after flashing newest tweakstock. My home has a strong signal and my bedroom is sometimes 4G so I don't believe the signal was low, unless the transition between radios killed it. However, it wasn't a problem 3 weeks ago.
I did freeze SDM and noticed some improvement. Buhohitr, did you mean freeze Google services framework?
Battery usage seems to be normal for now. I am noticing Dolphin is no Singer sucking down 35% or more since I switched to Mini. It doesn't even show up on the list.
I'll see how it goes today and report back on wakelocks. If it doesn't get any Beyer ima Odin to stock and root/flash tweakstock again.
Also, the battery doesn't drain unusually fast wile in use, browsing, music, etc. But when it sits it drains at 3-4% an hour.
Click to expand...
Click to collapse
To disable Google Service, go to settings -> location&security and uncheck Google service. Do not freeze Google framework. Also seems like your phone is not in deep sleep, please install "battery saver" by Antutu and let it works for 24 hrs, you should see huge different when your phone is sleeping. BTW what kernel are you using? If you're using PBJ kernel you can install "CPU tuner" to further keep your phone in deep sleep. I'm talking about 1% for 3 hrs sleeping.

I'm curious as to what Battery Saver actually does. The app's market page doesn't say. I'd be curious if it would interfere with my IMAP push email or SetCPU's overclock settings.

ewh1292 said:
I'm well aware of the post of Dianne Hackborn debunking the myth of wiping the battery stats; however, if you actually read the post on the steps to calibrating your battery, it's not just wiping your battery stats. There's actually a few more steps involved. You're right though, if you just wipe the battery stats and expect better battery life you're just wasting your time.
Sent from my Tweaked Droid Charge using XDA App
Click to expand...
Click to collapse
I've done that and never seen an actual difference. Like I said before, I have no reason to believe that any of it is anything other than placebo. My normal daily variability in use is more than enough to account for any perceived differences. On top of it all, bump charging is not good for a Li-Ion battery, so if anything, those instructions are a good example of how to lose long-term battery life for short term gain.

shrike1978 said:
I've done that and never seen an actual difference. Like I said before, I have no reason to believe that any of it is anything other than placebo. My normal daily variability in use is more than enough to account for any perceived differences. On top of it all, bump charging is not good for a Li-Ion battery, so if anything, those instructions are a good example of how to lose long-term battery life for short term gain.
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Click to collapse
Personally, I believe that most of the time the procedure does nothing. I think there are times, though, that corrupt data gets into the battery stats. For instance, I had an app lock up my phone and force a hard boot. When the phone came back up, it showed 22% more battery than it had previously. I believe that bad data such as this can over time affect how Android reads your battery life. In that instance, I believe clearing battery stats would help. I don't think doing it just because a new ROM was flashed actually does anything, though.

Wiping battery stats?

Does wiping battery stats too often due to flashing alot of roms reduce stock battery performance ?? Being curious..
Sent from my HTC Sensation Z710e using xda premium

No. The battery stats file is only used for determining battery drain. It does not have an effect on battery life one way or the other.

dallashigh said:
No. The battery stats file is only used for determining battery drain. It does not have an effect on battery life one way or the other.
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Thanks and while were at it dont wanna open a new thread is there any script for disabling the charging led ?? It gets very annoying at night in the bedroom :/
I remember i had such a script on my old x10 ... Thanks in advance
Sent from my HTC Sensation Z710e using xda premium

wiping battery stats does nothing to your battery and actually the battery stats are wiped automatically every time u fully charge ur phone:
Dianne Hackborn said:
Deleting it is not going to do anything to make your more device more fantastic and wonderful... well, unless you have some deep hatred for seeing anything shown in the battery usage UI. And anyway, it is reset every time you unplug from power with a relatively full charge (thus why the battery usage UI data resets at that point), so this would be a much easier way to make it go away.
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source: Dianne Hackborn - Android Framework Engineer on Google+

PuscH said:
wiping battery stats does nothing to your battery and actually the battery stats are wiped automatically every time u fully charge ur phone:
source: Dianne Hackborn - Android Framework Engineer on Google+
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Click to collapse
If the battery stats get wiped every time it hit 100 how one can keep the same battery life daily ?
Sent from my HTC Sensation Z710e using xda premium

The only way to really preserve a battery is to fully discharge, fully charge. Mine was going great until I slacked on it. I started only charging a little, fully charging from 40%, etc etc. Now, I'm on 100% for two hours. Then I drop fast to about 80%. Then I float around 80 to 60% for a few hours but once I go below 60%, boom, 20%. The last 20% go quick too.
Don't get me wrong, my battery life is basically the same, but now it's really inaccurate. If you start to feel this, the best thing you can do is fully charge, fully discharge. Do that a lot, over and over. It might help correct it, might not.
But to reiterate, no, wiping battery stats does nothing.

sshede said:
The only way to really preserve a battery is to fully discharge, fully charge. Mine was going great until I slacked on it. I started only charging a little, fully charging from 40%, etc etc. Now, I'm on 100% for two hours. Then I drop fast to about 80%. Then I float around 80 to 60% for a few hours but once I go below 60%, boom, 20%. The last 20% go quick too.
Don't get me wrong, my battery life is basically the same, but now it's really inaccurate. If you start to feel this, the best thing you can do is fully charge, fully discharge. Do that a lot, over and over. It might help correct it, might not.
But to reiterate, no, wiping battery stats does nothing.
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Okay thanks alot but can a custom rom really make that much difference on battery life's performance ?? On my old x10 no matter how many scripts tweaks for batttery they would add i would always get same battery life is it the same here ?
Sent from my HTC Sensation Z710e using xda premium

[Q] battery calibration

Hello,
I am trying to install some custom ROMS onto my phone and I just found one that I want to use. But I did read something that you should recalibrate your battery after installing custom ROMS. Is this true?
And my 2nd question is how to do this. Because I found an app: "Battery Calibration", but I don't know if this will do the trick. I know you can calibrate the battery with Clockwork too, but is this the same as the app?
Thanks in advance
Mathi

The purpose of recalibrating the battery is too get an accurate estimate of battery life. When you switch roms the processor usage changes. Your cell phone doesn't recognize this though and continues to estimate according to the old ROM usage.
I don't know about the apps, i've always done it the manual way.
Sent from my DROID BIONIC using Tapatalk

battery Cal.
this app works if you follow the 3 steps, charge to 100% then calibrate it unplug your phone then let it discharge fully then when you recharge it don't unplug it until it hit 100% for the second time then you should notice a slight improvement in your phones battery life i am sure the app and cwm method are similar, but with this app you should have no problem its really easy to use, hope this helped, happy tweakin

Hans5849 said:
The purpose of recalibrating the battery is too get an accurate estimate of battery life. When you switch roms the processor usage changes. Your cell phone doesn't recognize this though and continues to estimate according to the old ROM usage.
I don't know about the apps, i've always done it the manual way.
Sent from my DROID BIONIC using Tapatalk
Click to expand...
Click to collapse
How do you do it manually? Let it complete drain out and fully charge ?

From the recovery menu.
Sent from my DROID BIONIC using Tapatalk

All sources have said that Battery Calibration is reliable.
Also keep in mind that with Li batteries, every time the battery dies, its life is shortened by a small amount; therefore, every time you drain it completely, you're actually losing a little bit of battery life.
Other than that, I would be that Google can pull up quite a few results.

According to Google dev blog, wiping batterystats.bin is unnecessary and is in fact useless. You can Google for the link....
Sent from my PC36100 using Tapatalk 2 Beta-6

everytime i flash a rom also never do the battery calibration,it is necessary?

weiloon1234 said:
everytime i flash a rom also never do the battery calibration,it is necessary?
Click to expand...
Click to collapse
Not necessary at all, when you charge your battery 100% its already calibrated (status refreshed)

I've been using the battery calibration app ever since I started flashing ROMs and have done it every time I flash a new ROM. Can honestly say I notice a difference. Not always immediately as its advised to do a couple of full drain recharges before assessing your battery life

[Q] Battery Drain *Please Read*

I love to flash different roms from the devs here on this sensation forum, but when I do try anything thats AOSP Or that AOKP even miui it seems like my battery drains faster then it does on the htc stock roms. I would love to try to Jelly Bean roms that im sure are gonna start popping up very soon but afraid they will give me the same results in battery. anything i could do to fix it?

After every new rom flash you should drain your battery to under 10% then give it a full charge and wipe the battery stats from recovery. This is to calibrate your battery. By doing this the new rom gets to know your battery more or less, and will give you a much more accurate usage and drain.
Sent from my HTC Sensation 4G using xda app-developers app

Sloopjoshb said:
After every new rom flash you should drain your battery to under 10% then give it a full charge and wipe the battery stats from recovery. This is to calibrate your battery. By doing this the new rom gets to know your battery more or less, and will give you a much more accurate usage and drain.
Sent from my HTC Sensation 4G using xda app-developers app
Click to expand...
Click to collapse
Please stopping spreading this FUD. Don't wipe battery stats unless you have noticed a decrease in battery life that would give you reason to believe that your battery needs recalibration. Wiping stats too much does not extend battery life. If anything, it hurts it.
Sent from my HTC Sensation XE with Beats Audio Z715e using xda premium

I was merely passing along what helped my battery drain issues when dealing with a new rom and faster than normal battery drain. I have seen countless times this recommended in the forums here.
Sent from my HTC Sensation 4G using xda app-developers app

moto211 said:
Please stopping spreading this FUD. Don't wipe battery stats unless you have noticed a decrease in battery life that would give you reason to believe that your battery needs recalibration. Wiping stats too much does not extend battery life. If anything, it hurts it.
Sent from my HTC Sensation XE with Beats Audio Z715e using xda premium
Click to expand...
Click to collapse
I beg to differ; I've experienced it.
Here's something to read:
http://www.guidingtech.com/12739/android-battery-calibration-what-how/
The reason you wouldn't have experienced this problem is probably because some ROMs contain a "battery auto-calibration script".
My knowledge of this is quite limited, but I think the auto-calibration script is only present in Sense based roms.

battery drain
maybe i think your battery is old.
sensation is eating many battery.so your battery have many battery cycle.
If your battery is one year, you recommend to get a battery

moto211 said:
Please stopping spreading this FUD. Don't wipe battery stats unless you have noticed a decrease in battery life that would give you reason to believe that your battery needs recalibration. Wiping stats too much does not extend battery life. If anything, it hurts it.
Click to expand...
Click to collapse
Please stop spreading this FUD. Batterystats.bin has nothing to do with your battery life in any way, shape or form. It is there solely for reporting purposes.

It doesnt make the battery last longer, that is true. But it absolutely can help the battery percentage to be more accurately reported.
And since the phone will auto shut down at 1% battery, accurately reported stats CAN make the phone stay on longer even if nothing has been changed about how much current flows in and out of the battery.
That said, you cant judge battery life on a new rom for several discharge cycles. When I flashed cm9 the first day the battery lasted 12 hours. The second day it was 24. Now its 40 on average. Give it a week or so before deciding battery life suck.
Sent from a rebel ship by storing the message in an R2 unit. (Help me, XDA. You're my only hope)

No it can't. It has nothing to do with the battery %age.
It's (only) purpose is for the battery use info in settings.

Skipjacks said:
It doesnt make the battery last longer, that is true. But it absolutely can help the battery percentage to be more accurately reported.
And since the phone will auto shut down at 1% battery, accurately reported stats CAN make the phone stay on longer even if nothing has been changed about how much current flows in and out of the battery.
That said, you cant judge battery life on a new rom for several discharge cycles. When I flashed cm9 the first day the battery lasted 12 hours. The second day it was 24. Now its 40 on average. Give it a week or so before deciding battery life suck.
Sent from a rebel ship by storing the message in an R2 unit. (Help me, XDA. You're my only hope)
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Rusty! said:
No it can't. It has nothing to do with the battery %age.
It's (only) purpose is for the battery use info in settings.
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Click to collapse
What Rusty said. The file gets deleted after every charge to 100%, or drain to 1%. Then it gets made again. The only thing it does is provide the battery statistics in 'Settings' under 'Battery'. This myth was even listed on the front page.

with my myt4g when i had miui battery life was good without even waiting a few cycles. the sensation any stock or cooked sense roms i only notice a ggood battery life.i guess i'll just try to do what was suggested wait a few cycles before deciding battery life on the rom is no good

Rusty! said:
Please stop spreading this FUD. Batterystats.bin has nothing to do with your battery life in any way, shape or form. It is there solely for reporting purposes.
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http://www.androidcentral.com/wiping-battery-stats-doesnt-improve-battery-life-says-google-engineer
I stand partially corrected as I misremembered the content of this article. But I still stand by the fact that recommending a batterystats wipe after every flash to maximize battery life is complete FUD. The best thing you can do if and only if you suspect that your battery has become miscalibrated is to run it completely dead and then completely charge it without unplugging it until its done.

moto211 said:
But I still stand by the fact that recommending a batterystats wipe after every flash to maximize battery life is complete FUD.
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Correct, however that's not what you said, hence my repeat of your comment

Rusty! said:
Correct, however that's not what you said, hence my repeat of your comment
Click to expand...
Click to collapse
It's cool. Like I said, I misremembered regarding when batterystats should be manually wiped (never).
On a side note, my battery has lasted much longer now that I've completely stopped wiping batterystats. As has been stated by others, that file has nothing to do with actual battery life, but my perceived battery life is much better. My theory that by wiping batterystats manually, we hinder our phones ability to accurately report battery charge and adjust to maintain accuracy. So, if its inaccurately reporting 100% (fully charged) at 90% and reporting 1% (dead) at 10%, then almost 1/5 of the battery's full cycle is not being used. Therefore, when no longer wiping, the reporting can calibrate itself and "gain" back that 20%.
Sent from my HTC Sensation XE with Beats Audio Z715e using xda premium

Dummy’s Guide to Improve Battery Life of your Smartphone

No matter which phone you have, an iPhone or a GS3/GS2 or a Xperia device, you always fret over the battery life of your device! (Xperia owners a little more)
Instead of splashing out on expensive battery packs, here is a list of things you can do to get the maximum out of your battery :
1. It’s all about the Apps!
Many of the more than one million apps available to download to smartphones contain programming errors and software bugs that mishandle power control. This means your devices can remain active when they should be sleeping which further leads to unnecessary draining of your battery. Identify these apps! (Other apps like Carat can help you with that) and monitor there use!
Also, there is a good chance that there are apps running in the background of your phone that you think you closed or reappear each time you reboot your device. Fortunately, it’s easy to identify and correct this on the iOS and Android operating systems with a few easy steps. All open apps drain battery, so in this case, the lesser, the merrier!
2. The battery is always better on the cooler side!
Your smartphone most likely uses a Lithium Ion (Li-ion) battery. Be aware that extreme temperatures can negatively impact battery life so whenever possible keep your device in elements between 32 and 95 degrees Fahrenheit. While a frigid phone should reclaim its functionality once it returns to room temperature, an overheated device could permanently ruin your battery. Over the course of a year, prolonged exposure to climates above 95 degrees could reduce a phone capacity by as much as 35 percent.
Remove any protective cover or accessory every time your phone is being charged. When you’re walking around, keep your phone in a ventilated holster or belt clip rather than a sweaty hand or pocket. Over-charging will also contribute to an overheated phone.
3. Always look at the bright side of life! – well the screen actually!
Turn on Auto Brightness! Most phones have an ambient light sensor that adjusts the brightness of the screen based on the light around it (darker in dark places, brighter when there’s more ambient light) to both save battery and make it easier to see. Turn Auto-Brightness on and you’ll save battery because your screen will need to use less power in dark places.
If not, manually adjust your screen brightness according to your needs by accessing it from the settings menu.
4. Stay (dis)connected!
Transmitting data wirelessly takes battery and leaving Bluetooth on to accept incoming data at all times requires even more juice. Turn off Bluetooth except when you’re using it (duh!) to squeeze more juice from your battery.
3G can be a real battery zapper, especially if you’re using it in an area of marginal coverage. If in doubt, your phone probably has a toggle setting where you can set your phone to use only 2G, You will soon see an extension to battery life that way while not really compromising speed or service.
And disabling a 3G connection when not needed is just the start. If you know you’re going to be away from home or a known wireless Internet connection, turn off your Wi-Fi locator. Also, GPS is particularly handy if you find yourself navigating somewhere new, but don’t leave it on all the time if you’re not using it.
5. Zip it!
When in a meeting or a movie, switch your phone into silent mode. Unnecessary notifications will only lead to lesser battery life. Use a basic ringtone! Advanced ringtones can sound better, but the phone will die soon! Also, turning off location services and push-notifications is definitively a step-forward towards saving battery life!
If you discover your smartphone seems to be running out of battery life quicker than ever despite your habits remaining unchanged, it could be worth investing in a spare or new battery. It’s worth noting that aftermarket batteries not made by the original equipment manufacturers (OEMs) are considerably cheaper. They do, however, vary in quality. Some aftermarket batteries can be trusted, but be aware of ‘too good to be true’ prices for smartphone batteries on retailers like eBay. You could end up with junk, or worse, a faulty battery that permanently damage your device. Buy carefully and smartly from trusted retailers to be safe.

Underclock your phone to 800/1000Mhz (while you are travelling) cz SGSII can do most of the stuffs within that speed.
Use Custom kernel like siyah wch has better battery backup than stock
dont set min freq to 100MHz cz 200MHz is much more energy efficient than 100 & has more operationg power !!

Come on man, show some love for Celsius! Besides, it is what most of the world uses and is not seemingly arbitrary (or based on how cold it gets in the average american's basement)!
Anyway, well written guide, may prove useful for the lesser knowledgeable folks out there

Whilst I applaud you for putting this info together, it is not specific to the SGS2. This is SGS2 General. This kind of thread belongs General Discussion or at the very least in Android General (tho probably the former).

For 1. I would recommend using an app such as Go Power Master, as it tracks which apps are running as how much power they are using. Some apps are always running, but use very little power while others can use a lot while it is running.

Also, if this may be applicable:
If, after rooting or more likely that case after flashing a new rom, you often have battery reporting errors (as mentioned above), and re-calibrating the battery along with some steps I will outline for you below will ensure that your battery is getting a full charge, and the battery reporting accuracy is right on. As far as power cycling, I run my Atrix 2 in performance mode all the time, and with a CPU overclock of 1.25GHz and various tweaks, I have about a day an a half to a day and a quarter of full runtime from my battery. This is moderate to heavy usage (calls, emailing, text, gaming, web browsing, etc.) so you should have no problems getting acceptable battery performance after following these steps:
1. Take the case off your device (one of the latter steps involves taking the battery out from the phone while it's plugged in. Make sure your case won't stand in the way.)
2. Install Battery Calibration app from the market
3. Plug in your device to charge while it's on, wait till it gets to a 100%
4. When the charge is 100%, open the BatteryCalibration app and lookup what the charge is in MV while at 100%. Write it down.
My Atrix 2 was showing ~3400MV while at 100%, which is definitely not the maximum capacity.
5. Discharge your device completely until it shuts off.
A good way of doing this quickly is by turning on wifi, and a video player.
6. Without turning on the phone plug it into a wall charger and let it get to 100%
7. When it's at 100%, without unplugging it from the wall charger, take off the battery cover, and take the battery out.
Your phone will "reboot" and show a Missing Battery icon.
8. Without unplugging the phone from the wall charger or turning it on, put the battery back in and wait until the phone recognizes the battery.
9. Your battery should now be recognized by the phone, and showing a charge % significantly lower than 100%.
Mine showed only 5%.
10. Let it sit there charging for 2-3 hours (or more).
My phone wouldn't charge past 10%, but yours might. The numbers don't matter much as the phone is definitely getting additional charge that could have been lost while flashing ROMs, etc.
11. After 2-3 hours (or more), turn the phone on while holding the volume down button and get into CWM.
Do not disconnect it from the charger still!
12. Wipe battery stats in CWM, reboot.
Do not disconnect it from the charger still!
13. When the phone turns on, go into Battery Calibration app again and look up your MV numbers -if you were like me, they should be significantly higher than before. After this whole process I had 4351MV at 100%, comparing to 3400MV before calibration.
Do not disconnect it from the charger still!
14. Before going to sleep - Install Watchdog Task Manager Lite from the market. Go into it's preferences, set CPU threshhold to 20%, check "Include phone processes", check "Monitor phone processes", check "Display all phone processes", set system CPU threshhold to 20% as well.
Do not disconnect it from the charger still!
15. Make sure your wifi and data connections are off. Now finally unplug the phone from the charger.
Go to bed, let your phone sleep too.
16. Success! Next morning check where your battery % is at and if you followed the instructions correctly / got lucky like me, your battery life should be 90% or more.
I went to bed with 98% and woke up to 94%. So, I consider this mission a success.
Sent from my SAMSUNG-SGH-I747 using xda premium

A samsung developer actually said that whiping battery stats doesn't matter at all, it was on the XDA frontpage some time ago

AOKP undercloking
sekhargreen said:
No matter which phone you have, an iPhone or a GS3/GS2 or a Xperia device, you always fret over the battery life of your device! (Xperia owners a little more)
Instead of splashing out on expensive battery packs, here is a list of things you can do to get the maximum out of your battery :
1. It’s all about the Apps!
Many of the more than one million apps available to download to smartphones contain programming errors and software bugs that mishandle power control. This means your devices can remain active when they should be sleeping which further leads to unnecessary draining of your battery. Identify these apps! (Other apps like Carat can help you with that) and monitor there use!
Also, there is a good chance that there are apps running in the background of your phone that you think you closed or reappear each time you reboot your device. Fortunately, it’s easy to identify and correct this on the iOS and Android operating systems with a few easy steps. All open apps drain battery, so in this case, the lesser, the merrier!
2. The battery is always better on the cooler side!
Your smartphone most likely uses a Lithium Ion (Li-ion) battery. Be aware that extreme temperatures can negatively impact battery life so whenever possible keep your device in elements between 32 and 95 degrees Fahrenheit. While a frigid phone should reclaim its functionality once it returns to room temperature, an overheated device could permanently ruin your battery. Over the course of a year, prolonged exposure to climates above 95 degrees could reduce a phone capacity by as much as 35 percent.
Remove any protective cover or accessory every time your phone is being charged. When you’re walking around, keep your phone in a ventilated holster or belt clip rather than a sweaty hand or pocket. Over-charging will also contribute to an overheated phone.
3. Always look at the bright side of life! – well the screen actually!
Turn on Auto Brightness! Most phones have an ambient light sensor that adjusts the brightness of the screen based on the light around it (darker in dark places, brighter when there’s more ambient light) to both save battery and make it easier to see. Turn Auto-Brightness on and you’ll save battery because your screen will need to use less power in dark places.
If not, manually adjust your screen brightness according to your needs by accessing it from the settings menu.
4. Stay (dis)connected!
Transmitting data wirelessly takes battery and leaving Bluetooth on to accept incoming data at all times requires even more juice. Turn off Bluetooth except when you’re using it (duh!) to squeeze more juice from your battery.
3G can be a real battery zapper, especially if you’re using it in an area of marginal coverage. If in doubt, your phone probably has a toggle setting where you can set your phone to use only 2G, You will soon see an extension to battery life that way while not really compromising speed or service.
And disabling a 3G connection when not needed is just the start. If you know you’re going to be away from home or a known wireless Internet connection, turn off your Wi-Fi locator. Also, GPS is particularly handy if you find yourself navigating somewhere new, but don’t leave it on all the time if you’re not using it.
5. Zip it!
When in a meeting or a movie, switch your phone into silent mode. Unnecessary notifications will only lead to lesser battery life. Use a basic ringtone! Advanced ringtones can sound better, but the phone will die soon! Also, turning off location services and push-notifications is definitively a step-forward towards saving battery life!
If you discover your smartphone seems to be running out of battery life quicker than ever despite your habits remaining unchanged, it could be worth investing in a spare or new battery. It’s worth noting that aftermarket batteries not made by the original equipment manufacturers (OEMs) are considerably cheaper. They do, however, vary in quality. Some aftermarket batteries can be trusted, but be aware of ‘too good to be true’ prices for smartphone batteries on retailers like eBay. You could end up with junk, or worse, a faulty battery that permanently damage your device. Buy carefully and smartly from trusted retailers to be safe.
Click to expand...
Click to collapse
Actually I underclock my GS2 to 800Mhz thanks to an AOKP Rom and my battery last one hour or one hour and a half more, which is great when you just have 7/8 hours of battery life normally. It didn't really affect the use of common apps, but of course if you want to play big 3D games, I suggest you to clock it a its original rate (1.2Ghz for the GS2 for example).
---------- Post added at 01:26 PM ---------- Previous post was at 01:21 PM ----------
Neefy said:
A samsung developer actually said that whiping battery stats doesn't matter at all, it was on the XDA frontpage some time ago
Click to expand...
Click to collapse
Yes I think so because this is just statistics, it will not affect the actual battery life of the phone.

Apex_Strider said:
Also, if this may be applicable:
If, after rooting or more likely that case after flashing a new rom, you often have battery reporting errors (as mentioned above), and re-calibrating the battery along with some steps I will outline for you below will ensure that your battery is getting a full charge, and the battery reporting accuracy is right on.
<Snip>
Sent from my SAMSUNG-SGH-I747 using xda premium
Click to expand...
Click to collapse
This is bump charging and while it does work, it is not good for Li-on batteries. I'll find the link and edit it back in but bump charging will shorten the life of your battery due to inconsistent charge cycles.
Neefy said:
A samsung developer actually said that whiping battery stats doesn't matter at all, it was on the XDA frontpage some time ago
Click to expand...
Click to collapse
This is from my battery guide. OP (or anyone for that matter), feel free to check it out. There is far more information, apps, deep memory management trick,... Link is in my signature.
Batter Calibrator –
<Snip>
**Note that this can be done two other ways. You can boot into CWR or Custom Recovery and go to Advanced Settings and there will be the Wipe Batterystats.bin option. Or you can do it manually by going into /data/system/ and deleting the batterystats.bin in there. Any of the three methods work to get the entirely same result in the end. I just like using the app or manually myself. **
<Snip>
Recently there has been information debunking this process. I will post it below, however I know what it says, but I also know what I've seen/experienced too. Here is the post by Dianne Hackborn, a Google Dev on her G+ account.
Dianne Hackborn - Jan 12, 2012 - Public
Today's myth debunking:
"The battery indicator in the status/notification bar is a reflection of the batterystats.bin file in the data/system/ directory."
No, it does not.
This file is used to maintain, across reboots, low-level data about the kinds of operations the device and your apps are doing between battery changes. That is, it is solely used to compute the blame for battery usage shown in the "Battery Use" UI in settings.
That is, it has deeply significant things like "app X held a wake lock for 2 minutes" and "the screen was on at 60% brightness for 10 minutes."
It has no impact on the current battery level shown to you.
It has no impact on your battery life.
Deleting it is not going to do anything to make your more device more fantastic and wonderful... well, unless you have some deep hatred for seeing anything shown in the battery usage UI. And anyway, it is reset every time you unplug from power with a relatively full charge (thus why the battery usage UI data resets at that point), so this would be a much easier way to make it go away.
Click to expand...
Click to collapse
Click to expand...
Click to collapse

Neefy said:
A samsung developer actually said that whiping battery stats doesn't matter at all, it was on the XDA frontpage some time ago
Click to expand...
Click to collapse
The point of doing so is if you happen to get incorrect battery reporting, which DOES occur in certain capacities. So, in my book as well as many others, it does matter for these situations. If only one developer told you the world was flat, would you believe that also?
Sent from my SAMSUNG-SGH-I747 using xda premium

Thanks for the useful information!

Great information that applies to any phone, thank you.
Sent from my SPH-D710 using xda app-developers app

sekhargreen said:
No matter which phone you have, an iPhone or a GS3/GS2 or a Xperia device, you always fret over the battery life of your device! (Xperia owners a little more)
Instead of splashing out on expensive battery packs, here is a list of things you can do to get the maximum out of your battery...<snip>
Click to expand...
Click to collapse
Apex_Strider said:
Also, if this may be applicable: <snip>
Sent from my SAMSUNG-SGH-I747 using xda premium
Click to expand...
Click to collapse
Great info/tips from both members above. Thanks button thanked for both!

Fosho bro thanks a lot...simple tips
Sent from my One X using xda app-developers app

Actually I could only save battery on my MEIZU by underclocking & battery saver app.
Thanks for your infos, I'll give some of them a try now (again )

Nice information... thanks for sharing..

You can also buy a better battery for your phone. They normally are cheap too
Sent from my HTC Sensation Z710e using xda app-developers app

I just turn on power saving mode. But I still need to recharge my phone daily, once in two days if I'm lucky. But after reading this topic I will see if I can scratch those pesky powerhungry little demons.
Sent from my GT-I9300 using xda app-developers app

Apex_Strider said:
The point of doing so is if you happen to get incorrect battery reporting, which DOES occur in certain capacities. So, in my book as well as many others, it does matter for these situations. If only one developer told you the world was flat, would you believe that also?
Sent from my SAMSUNG-SGH-I747 using xda premium
Click to expand...
Click to collapse
Battery stats has nothing to do with battery reporting. And it was an engineer from Google's Android team that debunked the battery stats wives' tale.
So yeah, folks probably should believe a recognized subject matter expert when they clearly and concisely debunk misinformation such as the advice to wipe battery stats.
Also, it bears mentioning that the os clears battery stats upon every reboot, making the advice to do so even more pointless than it already is.
Sent from my Galaxy Nexus using Tapatalk 2

Great tips...definately learned something! Much appreciated!!
Sent from my SGH-T989 using xda app-developers app