[Sony Xperia S, Acro S, Ion] thanitos:
So, some may have noticed two things about your phones; 1) You have 'Android OS' using high amounts of your data as well as your battery. 2) General day to day use drains your battery very quickly. So what are you to do?

First lets address our day to day use of our phone.

Start by getting an app like Brightness Level. I use this app to keep my phones screen at 0 during the night and 25% during the day when the sun glare makes it hard to read.

Now we move into the data usage from apps and wakelock issues. This can usually occur from apps such as facebook looking to update while your phone is in your pocket. This uses data as well as wakes your phone up causing it to use more battery then if it were asleep. For this problem I recommend Juice Defender Ultimate, now you can get the free version but you wont have access to all the next steps but you will still see results.

Firstly, JD will refer to JuiceDefender

1) You will need JD anything above the free version (Google it)

2) Open JD and go to the "Status" Tab at the top

3) Enable

4) For "Profile" Choose Customize

5) A "Settings" Tab should Appear at the top, if not, close JD and re-open it.

6) Mobile Data can be Enabled or Disabled here as well as WiFi and Location

a) Turn them on and off for what you want, if you want Mobile Data and Wifi to turn on and off on specific apps you can just leave them Enabled.

b) "Schedule" Turning this on will turn on your data every 5m(minutes), 15m, 30m, 1h(hour) or 2h so it can push email and other apps you have set to use data.

c) "Night" this you can use to turn off data while you sleep and for how long you want it off

d) "Apps" You can enable this setting to pick apps that are allowed to use data or turn it off to let them run as they usually do.

e) "Interactive" will pop up a window while JD is in the background and you can pick what JD allows the app to do (will go over more of that soon.)

f) "Configure Apps" We will open this to turn app data on/off on when you have it open, on all the time.

1a) Tap "Configure Apps"

a) "Internet Apps" Apps that use the internet

b) "Configured Apps" These apps are configured by you already.

c) "All Other Apps" These apps usually do not need the internet so they do not need to be configured.

2a) Move to any App under "Internet Apps" and tap it

3a) What do the taps mean?

a) "Enable" This app is enabled, when it needs data it will only use data when you have the app opened.

b) "Enable/Screen off" This app is on and using data while the screen is off and or while the app is opened.

c) "Disabled" This app will never use data

d) "Do Nothing" The app will use data when it needs it, JD won't bother its operation.

4a) Examples

a) "Pandora" I have this app set to Enable/screen off so while I have the app running in the background it will still use data, or while the screen is off it will use data.

b) "Ebay" This app is Enabled, when I open the app and I am looking at it it will use data, but if I hit the home button it stops using data, wont use data while screen is off.

c) "AccuWeather" Disabled, this app will only use data when my Schedule turns data on for ALL items on my phone every 2 hours, it will then update anything it needs to then end data usage for two more hours.

d) "Root Browser Lite" Do nothing, This app will use data whenever it wants regardless of JD rules unless data is disabled.

Lastly, what about that pesky "Android OS" ? While people speculate what "Android OS" actually entails we will just go with what stops its killer data and battery drain.

Open up Play Store then hit your settings button, Check update over wifi only, This way we don't have apps updating all the time using a lot of data, this isn't a big necessity to do this but I do it just to be on the safe side.

Now close Play Store and go to Settings> Data Usage then hit your settings button on your phone, Check Restrict Background Data.

If you look at the Android OS in your data usage chart you will see almost all of its activity happens in the background. Restricting Background Data limits its ability to use up all your data. From doing this, last month my Android OS used 286MB in just 5 days, now it used only 80mb in 5 days. From December 5th to January 5th it used a total of 2.34 gigabytes of my data alone. This is my MAIN data culprit and the bane of multiple peoples limited data.

You may also want to go to Settings> Backup & Reset and uncheck Backup my data, Some speculate this also leads to android OS using a lot of your data.

So these are just a few things I found as I googled and searched the forums and the internet to help me save battery life, not meant to be a huge in-depth top of the line guide, more of just a general education plan. Good luck all with your battery saving en-devours, and of course if you have anything you do to save a little juice or kill that pesky Android OS bug let us all know.

Edit #1- (Some info on Android OS bug and Gapps) [Source- http://mobility.forumsee.com/a/m/s/p12-9475-0182175--android-enormous-data-usage.html]

"The Android OS drain is a bug. That is why Google is about to push a patch 4.2.2.However, if your having Android System drain, make sure you've opened all the following apps at least one time so they can sign in, regardless if you use them or not. As these are system apps, they will keep sys running until you sign in.

YouTube

Google Earth

Google + (I then disable all the sync stuff in g+ settings)

Chrome

Currents

Maps

Play Music,Magazines, Books, Music"