[Samsung Galaxy Nexus] ZafarHSayed:
[sorry for the HUGE post!! tl;dr at the end!]

Hi everyone, I am having a really REALLY bad problem managing my battery once I updated to 4.0.4. Now this is really weird because before deciding to flash the OTA (didn't get it myself, flashed it manually from a thread here) I was hearing how the battery is a lot better for some people and some lag issues were fixed. However, I'm noticing that these things actually got worse for me... maybe someone can help? I'm still on yakjuux (don't know why I didn't switch to yakju yet lol), and I'll start listing some of the issues I'm coming across...

Before manually flashing (when I was on 4.0.1), I used to leave home in the morning with ~85% battery and listen to music for my 1.5 hr commute to campus, and end up charging some time in the day from 30% to 70% before heading back home, listening to music again and then charging before I sleep from around 20% to 90%, and this repeated every day. My usage wasn't light either - I constantly text (and whatsapp), browse, make calls, check twitter, browse the 9gag app, listen to music, etc (no wifi, screen with 1 notch above the lowest brightness) and this worked for me every day. My phone only heated up slightly while charging while using it or after playing games for some time. I'm guessing this is normal for everyone. I never really encountered system lag either.

Now that I've switched to 4.0.4, I have to charge my phone on campus twice and both times to nearly max if I want to use my phone for anything on my return home, and before leaving home I need almost a full charge to not hit the red zone in my battery before getting to my campus. I noticed from the night I flashed it that my phone started warming up with the SLIGHTEST usage, and I mean like almost nothing.. having my screen on with the same brightness and wifi on at home warmed my phone up. Listening to music with the screen off on my train warmed the phone up. Reading a few tweets on wifi at home with the lowest brightness warms my phone. I don't get it... Due to all this my usage is severely reduced, and sometimes my phone is turned off for a few hours just to be able to make a call if I need to at a later time. I notice a lot of people are managing better battery than previous ota's but mine is significantly worse. I've literally watched my phone drain 5% battery while walking between two classes (not even a few minutes of walking..). Right now my brightness is at 0 (lowest), wifi is only on when I'm at home. I know some people have a battery drain issue related to losing their mobile signal but mine works fine. Even on idle, my phone drains quickly. In my first week on 4.0.1 I pulled 16 hours on semi-heavy usage and with maybe half of that I can't even do 2 hours with 4.0.4.

That is just the battery... there is lag for some apps now too. Temple Run used to lag when it was first released, and after an update it worked buttery smooth while on 4.0.1. Now, I'm lucky to avoid the obstacles because there is intense lag and freezing. The phone also heats up a ton while doing this (or anything else). A few days ago I had massive lag while texting, there was no haptic/visual feedback or response for 3-4 seconds then things started showing up... since then I think this has gone or maybe I notice it less with my reduced usage. I've also noticed that I get 1-2 less bars in wifi and 3g reception in my bedroom (where I used to get max usually before). I'm not sure if this is misrepresented or if I am actually accessing less of my available networks... although I never do lose my mobile network entirely. The performance of all my other apps is to the same level as before, or unnoticeably different. In my battery statistics I notice that the screen is using a lot less of the battery (compared to 4.0.1), but the android os takes about 40%. Is that normal?

I'd like to know if these issues are common for 4.0.4 (or is it because I'm on yakjuux?). I would try re-flashing the ota and see if it would get fixed but I kind of screwed up and didn't unlock my bootloader (didn't know the benefits of it at the time) and now I have no root. What fixes are available to me? I do not mind unlocking the bootloader now, I have all important things backed up anyway (its only media, lol).

I was thinking about using the GN Toolkit, but I figured I'd rather ask first (also gives others who might have this issue something to refer to). I guess I could use the toolkit to put 4.0.1 yakju on it and check for ota in settings, or just put 4.0.4 yakju right away if these issues are not present. At this point I do regret changing to 4.0.4, because I have to reduce my usage just to keep my battery going.. after not really gaining much, it was not worth it.. unless this can be fixed. I was thinking of re-rooting and flashing my original yakjuux 4.0.1 and staying there, or eventually change to yakju, but my bootloader is locked so that option is not available right?

Thanks in advance for any help anyone can provide, especially after reading this novel of a post.. lol :) I lost about 11% of my battery while typing this post, so yeah it is a big dumb problem.

tl;dr -- after switching from yakjuux 4.0.1 to 4.0.4 yakjuux, my battery is really crappy, maybe half as good as it was before. I am not rooted and my bootloader is locked still. What can I do?