Galaxy S II horrible battery life


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I just got my first smartphone today, the Galaxy S II. I actually work at AT&T and am still waiting on my employee line to activate, but I took the phone home early. So there's no service at the moment, but I've been using it on wifi. I already rooted it and installed UnNamed v2.2.1, which removes the junk AT&T bloatware and supposedly increases battery life. (Not worried about voiding warranty since 1. I didn't trip the flash counter and 2., I work there and can exchange it myself.)

1hr and 5 mins on battery caused it to go from 100% to 87%. Screen brightness is all the way down, bluetooth and GPS are off, and I don't even have any apps installed yet besides the ones that come with UnNamed, none of which are running.

Is it draining fast simply because I don't have service yet, and perhaps it's just trying to connect or something? I still have my old flip phone as an alarmclock with an old sim and it lasts about a week without service...so I'm not really sure what's going on.

The only thing I've done so far is wifi + browse phone / appstore. Within a couple of minutes, I saw it drop 1%. This can't be right. I wonder how long it would last playing a video or a game. Sheesh.

So yeah. Is this because the phone is not currently receiving service, or is it perhaps another thing entirely?

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So you've been playing with the phone with screen on for 1h and it dropped 13%? Sounds about normal then. LOL Welcome to Smartphones and huge 4.3" Super AMOLED LCDs!

You can't really tell battery life also after the first few hours of owning a phone because you usage is not "normal" compared to your old beater.

Put the device in Airplane mode also - and yes you can turn on wifi in Airplane mode - that'll save the device from scanning and trying to connect to AT&T all the time.

Your battery will drain much faster when it is searching for service. Try puting it in airplane mode and then manually switching on the wifi (this disables the phone radios)

Okay, got it. It just dropped to 86% by scrolling through my contacts for about 2 minutes. lol. Let's see what this airplane mode does.

Edit: @SHoTTa25, no, no, haha. It's only been on for a little over an hour. I've hardly used it. It's been in standby most of the time.

sounds like a bad flash or a wake lock trouble imho

airplane mode shuts the phone down !

no text no email no nothing lol

He doesn't have service yet so he's no doing no text or emailing anyways. But as already pointed out, you can still use wifi while on Airplane mode. That just turns off the 3G radio but you can still connect via wifi to get email if you haad that already all setup.

according to that so 5 minutes to loose 1% with the wifi/screen on. Dunno what you complaining about there :D Later in the week when you start using the phone like normal then you'll see how a normal day goes.

according to that so 5 minutes to loose 1% with the wifi/screen on. Dunno what you complaining about there :D Later in the week when you start using the phone like normal then you'll see how a normal day goes.

So this is normal? Wow. I can't imagine how awful it's gonna be when I actually have apps and service. Looks like I might have to buy that bigger official samsung battery, if they have it for the US version. Yikes.

Its the problem with unnamed rom. here are some who have this issue

http://forum.xda-dev...d.php?t=1335376

try cyanogenmod.

I was wanting to try cyanogenmod anyway. So how do I go about installing another OS rom/kernel? Just boot into CWM, wipe device, and the install the new one?

edit: Nevermind, I think I figured it out.

Please note from site - NOTE: This guide is only applicable for the international variants (GT-I9100, GT-I9100M, GT-I9100T) and not the regional variants.

http://wiki.cyanogen...ll_Update_Guide

Galaxy S II AT&T version guide

http://wiki.cyanogenmod.com/wiki/Samsung_Galaxy_S_II_(AT%26T):_Full_Update_Guide

Please note from site - NOTE: This guide is only applicable for the international variants (GT-I9100, GT-I9100M, GT-I9100T) and not the regional variants.

http://wiki.cyanogen...ll_Update_Guide

Galaxy S II AT&T version guide

http://wiki.cyanogen...ll_Update_Guide

Yep, I found the guide a couple of minutes ago. I'll report back once I brick it. lol. Thanks.

I was wanting to try cyanogenmod anyway. So how do I go about installing another OS rom/kernel? Just boot into CWM, wipe device, and the install the new one?

edit: Nevermind, I think I figured it out.

here is the rom just in case u were looking. http://download.cyanogenmod.com/?type=stable&device=galaxys2

i hope u figured it but if u have issues let us know.

here is the rom just in case u were looking. http://download.cyan...device=galaxys2

i hope u figured it but if u have issues let us know.

K-K-K-Kombo breaker!!!

http://download.cyanogenmod.com/?device=galaxys2att

That's the one for the AT&T version. :p

Sorry, but the usage is normal, generally depending on how you use your phone, you can expect to charge your phone every 1-2 days. Remember, the biggest drain on a battery is either when it's searching for a service, the wireless being on or when the screen is on. This is completely normal for someone who has just got their first smartphone, they always say "Why is the battery life so bad?", this isn't a dumb phone, the screens are bigger, they have WiFi, email, internet etc

If it's one for 5 minutes and it goes down 1% doesn't mean it'll do that in standby unless there is something that is keeping it awake.

Several factors here that you need to consider before complaining about battery life:

1. Usage/Screen Brightness: You just got the phone. In all likelyhood, you are going to play around with it almost every chance you get to change the settings and try new apps, which will drain the battery. Give it a week or two before you get used to the phone and the novelty wears off a bit before you finally get back to normal usage. Oh, and really consider using minimal screen brightness rather than auto brightness whenever you can. Just leaving the screen on in idle will drain your battery pretty quickly if brightness is set too high.

2. Rom: Not all roms are created equal and it is very easy to for a single bug to suck the life out the phone. Best to keep track of the xda thread for common issues as you are not likely to be the only one experiencing the same issue.

3. Kernel: Rom is only half the package. Flashing the right kernel, especially one that is coded properly and fine-tuned to balance performance and battery life will drastically improve the experience. Different roms usually are compatible with different kernals, so do some research on the best one.

4. Haptic feedback/animations: I would suggest turning down the haptic feedback to about 25% as it usually is all that that you need for regular use. Also, turn off screen animations, like for opening the app drawer, will also improve battery life as well.

5. Apps: Keep well in mind that when installing apps, manually go the settings and disable auto-syncing as it is unnecessary for most apps.

I have the international SGS2 and I can make it last 2 days on about 5 hours of screen time and moderate data usage. Then again, I don't make a lot of calls, most texting, emails, music, etc.

It's still dying just as fast even with wifi off and airplane mode on, so I'm just going to assume it's normal and switch back to unnamed. The organization of CM7 is horrible in comparison.

You can't really just hold it in your hand and tell whether it's draining faster or slower. The best way to check battery life is to max it out and then leave it alone for a few hours. The % loss per hour will be a concrete measure. Just be sure to you use the same method (wifi on, flight mode on, etc) for a consistent comparison. But again, don't expect to find the best one in a single day. It takes time. For now, just aim to get a rom that suites your personal ui preferences and themeing, and go from there.

Mine goes at about 1% per 60 minutes with data, wifi, and voice signal on. In full flight mode, it might last twice that.

That doesn't sound right. I have a Droid Incredible sitting here (also rooted, and loaded with CM7). With airplane mode on, and WiFi on, it will go for a few days easily (with email sync set to manual). Also, the Incredible is 3.7" and I have a 1750 mAH battery, but nonetheless, you definitely have something wrong with that phone. I had a Galaxy Fascinate (also rooted/rom'ed), and didn't experience that. Have you checked the battery stats (check in settings) to see what is eating up the battery?

That doesn't sound right. I have a Droid Incredible sitting here (also rooted, and loaded with CM7). With airplane mode on, and WiFi on, it will go for a few days easily (with email sync set to manual). Also, the Incredible is 3.7" and I have a 1750 mAH battery, but nonetheless, you definitely have something wrong with that phone. I had a Galaxy Fascinate (also rooted/rom'ed), and didn't experience that. Have you checked the battery stats (check in settings) to see what is eating up the battery?

You can't really just hold it in your hand and tell whether it's draining faster or slower. The best way to check battery life is to max it out and then leave it alone for a few hours. The % loss per hour will be a concrete measure. Just be sure to you use the same method (wifi on, flight mode on, etc). But again, don't expect to find the best one in a single day. It takes time. For now, just aim to get a rom that suites your personal ui preferences and themeing, and go from there.

Mine goes at about 1% per 80 minutes.

Alright. Well I went back to UnNamed for now. I really like the UI and extra options. I'll keep monitoring the idle hourly usage.

That doesn't sound right. I have a Droid Incredible sitting here (also rooted, and loaded with CM7). With airplane mode on, and WiFi on, it will go for a few days easily (with email sync set to manual). Also, the Incredible is 3.7" and I have a 1750 mAH battery, but nonetheless, you definitely have something wrong with that phone. I had a Galaxy Fascinate (also rooted/rom'ed), and didn't experience that. Have you checked the battery stats (check in settings) to see what is eating up the battery?

Display is 58% and Android system is 21%. Battery life is at 70% now, vs 87% when the thread started. I guess that's sort of normal for how long I've been messing with it. I'll see how it holds up for the next couple of days.

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