[Motorola Droid RAZR] brainwash123:
Hello all,

I got frustrated with the unrealistic 10% step battery reporting and unknown battery eaters so below are the steps I've taken. Scroll down to skip the initial stats.

First you should study http://xdaforums.com/showthread.php?p=27927999 and use the tips given there. I will focus on more internal stuff that is in part specific to RAZR. This guide is for you if you see high battery usage of "Android OS".

Suggested apps:

- Circle Battery - free - it will report the real battery percentage as well as battery temperature. The higher the temperature the slower the phone will charge

- BetterBatteryStats - paid on the Market or free here on XDA

Measuring:

I would suggest to do measure any improvements during idle usage. It's a lot easier to track down the hungry settings.

Also, you should fully charge your phone between measurements so the battery stats get reset. There are also other ways to do it.

Establish the baseline usage of your phone with the current setup. You can assume a linear battery run down so you can extrapolate from the REAL 20% of battery usage that your phone will last 5 times more.

Go to Settings=>Battery and write down which apps used most of the battery.

If screen and cell standby are the biggest ones then you are mostly ok: cell switching for 2G->3G->4G switching is eating a lot of battery.

You can either: use WiFi for data (if available and has a good signal) or disable data altogether while in the problematic area. You can also disable high-speed connections and remain on 2G.

If Android OS is eating the most then write down the stats and read on.

Remove ALL the widgets on the home screen. Measure battery usage again as above. If still not satisfied, keep widgets removed and read on.

Go into Settings=>Accounts and disable unneeded syncing of accounts. You can manually sync your Drive app for example or the Books. For example, I have left only Browser, Calendar, Contacts, Chrome for my google account.

Set your email checking frequency to 1 hour for all email accounts, don't use push.

Measure and move on if not satisfied.

Open BetterBatteryStats and set the second drop-down as 'Since Unplugged'.

Select "Partial Wakelocks" from the first combo and study the output. It will tell you which apps are waking up the phone.

Select "Alarms" from first combo and study which apps are periodically waking up the phone to process data. Mostly email, calendar, facebook, but you might have a few surprises. Clicking on an alarm will show how many times the application has woken up the phone and how long it kept it up. There is a lot more information here on the forums about BBS usage so do a search.

Some other thing: high data usage would most like mean high CPU and battery usage. A friend with SGS noted that the News&Weather app ate 300MB of data in two days. While transferring, the phone is most likely not idle. You can check data usage in Settings=>Data Usage. From the options menu you can also enable the WiFi statistics and check those as well.

Hopefully by now you have identified what's keeping eating your battery so let's see the:

Actions

Is the app needed? If not, just disable it through Manage Apps=>App Info=>Disable

Does the app really need the data connection? If not, go to the data settings, set a limit to the data plan and you are able to disable background data for some apps.

Find battery-friendly alternatives for applications and widgets.

Use Tasker to set profiles. For example I'm automatically opening up the WiFi while near one of my home GSM Cells. This uses minimal battery as opposed to a GPS positioning. I'm disabling all data connections during night time, also good for sanity.

There's a lot more info about Tasker and building profiles on the Internet.

You can also use the built-in Smart Actions app, but it's not so flexible.

Increase the WiFi search delay from 45s to 90s or more.

[TODO: more measures]

Recommendations

On my phone MotoEmail was eating a lot of battery, even more while set as a widget on the home screen. I've replaced it with 'Inverted Mail', it's the stock ICS Google Email app with inverted colors. To replace it you have to use Root Explorer (or similar), set the /system as r/w and rename /system/app MotoEmail.apk to *.bak, copy the inverted app as MotoEmail.apk and install it. You will lose some options such as gestures, widget style and probably more.

Put a leash on location-aware apps like Latitude and Social Location, they will send a lot of work to Google Maps.

Use darker themes and low brightness for improved screen-on life.

Check live wallpaper CPU usage by enabling the checkbox inside the developer settings.

Give up your microSD card if you can live with 16GB.

Disable touch sounds and haptic feedback.

Disable automatic market update checking and notifications. Still at notifications, disable the notifications you don't really need.

Watch out for maps that automatically update graphically. Google maps live background or widget is nice but it kills the battery and performance.

Other stuff

There are also a lot of other options but I have not been able to confirm them on myr Razr since I have only had it since last week. These include underclocking, raising minimum CPU speed (worked on my other phones), using different colors for background and theme, disabling some logs, modifying buffer sync time, boot scripts etc.

Feel free to add to this thread by listing your changes that improved battery life.

TL;DR

Install Circle Battery Widget and BetterBatteryStats