[TESTING] Battery Drain Optimization on the Optimus V - Optimus One, P500, V General

Part 1
Intro:
I took my Optimus V and spliced in a multimeter between the battery and the phone. All it took was double sided tape and tinfoil. With the battery installed in the phone, the foil directs the positive terminal of the battery out of the phone, through a multimeter, and back into the phone through a second piece of foil that is separated from the first with double sided tape.
This enabled me to monitor the actual battery draw. I installed various roms and monitored the battery usage under certain conditions. I focused on the lower end of battery usage (airplane mode, stand by, under-clocking) because that is the focus of most smartphone users, getting the most battery life. I had a resolution of 1mA. So keep that in mind when looking at the results. A value of 2mA means the actual value might be 50% more or less.
Setup:
Each rom was a fresh flash. The only apps installed were google's. Airplane mode was toggled in order to remove the effects of the 50% Time Without Signal issue. The Rodimus rom had setCPU added to control CPU speeds. Besides changing the relevant settings, nothing in the system was touched. A steady 3G and CDMA signal was available during testing. A Wifi signal with WPA2 protection was used in the Wifi tests. A google account was also added to all the roms and background information was left enabled. Syncing was turned off. All of the values measured fluctuated somewhat during testing. Approximations had to be made as to the average stable values.
Roms Tested:
Stock
Rodimus 20/03/2011
Zefie's CM7 01/03/2011
aospCMod CM7 24/03/2011
Testing Conditions:
Powering on
Airplane Mode - Standby - Underclocked to 122MHz
Airplane Mode - Screen Brightness 0%/100%/50% *
Wifi - Standby - 122MHz
3G - Standby - 122MHz
No Data - Standby - 122MHz
Wifi - Standby - 600MHz
3G - Standby - 600MHz
Airplane Mode - Standby - 600MHz
Wifi - 600MHz**
3G - 600MHz**
Airplane Mode - 600MHz**
*CPU set to 600MHz
**Unless noted otherwise screen brightness was set to 25% and the phone was left on its homescreen.
***Because of a lack of CPU control, the stock rom could only be tested at 600MHz
Results:
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50% Results:
I also tested the 50% Time Without Signal issue using Rodimus. Airplane mode was not toggled after a fresh install. 50% issue was confirmed. Wifi was then setup and then put into standby mode for the measurement. Then Wifi was disabled and 3G automatically connected. The 50% issue was again confirmed to be in effect. The phone was then put in standby mode for the 3G measurement. Data was then disabled and put back into standby for the last measurement.
Wifi: 5mA
3G: 300-2mA****
No Data: 2mA
****When 3G was enabled and the phone put into standby, the current draw would fluctuate from 2mA to 300mA every few seconds. This was not seen in tests where airplane mode was toggled on and off after boot.
Conclusions:
At first glance there does not see to be much difference between the roms. Remember though that all of the 2mA values have an error of 50%. So there could be a 3 fold difference between some of those values. If I had a more sensitive multimeter, we could get better results.
One notable difference is between the roms when using Wifi on standby. The stock rom and Rodimus both draw significantly less power than the CM7 roms. This seems to be an unresolved bug with CM7. Also worth noting is that 3G draws significantly less power than Wifi regardless of Rom. Keep in mind that no data is being transferred while the tests are occurring besides whatever the background data uses.
It looks as though the 50% Time Without Signal issues does effect battery life when on 3G. The phone appears to be doing some activity every few seconds. Take note that I only tested it on Rodimus.
Using a current draw of 3mA, the 1500mAh battery could last as long as 500 hours. Of course, even in standby and underclocking, the current draw will randomly jump to 100mA every now and then on all of the roms. A more practical estimate at the battery life is 100 hours. That gives an overall average power draw of 15mA.
I was hoping underclocking would show a significant decrease in power use, but my resolution was not good enough to pick up a difference. I'm sure an advantage still exists, but I can't prove it with the equipment I have. The effects seem to be limited to less than 1mA. This is worthless when using the phone, but when in standby, the savings could be significant.
Hopefully these values will help you out as well as the developers. Let me know your thoughts. Note that all of these values are current draw directly from the battery. Another user on Howard forums tested the draw from the USB port which occurs at 5V and doesn't account for the loss due to stepping down the voltage.
Winners:
Leaving 3G on during standby - No clear winner among the roms because of testing equipment limitations but by far better than leaving your phone on Wifi
Airplane mode during standby - No clear winner again
Leaving Wifi on during standby - Rodimus
Not in standby but idle - Stock rom

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Part 2
Setup:
To summarize my procedure, I splice equipment in between the battery and the phone so that I can monitor how much battery is being used at any given time. I install various roms and test how much the battery is drained using different features. This time around I used more sensitive equipment that gave a resolution of 0.01mA (100 times higher resolution than before!). My approach to the calculations was different this time too. Instead of just considering the current, I also recorded the voltage across the battery. In this way, I can calculate the instantaneous power draw.
Each rom was a fresh install. After the install, a Wifi network was added. Wifi sleep policy was set to never sleep. A google account was added. The rom was then restarted and airplane mode was toggled to remove the 50% TWS bug. No other settings were tampered with, including CPU speeds. Besides the typical tests from last time, I also included:
Downloading - Docs2Go using Wifi and 3G
Checking Email using Wifi and 3G
Calling Voicemail with 3G and Wifi turned off
Where (the app) Running
Where running in the background while on the Homescreen
Where running in the background while on Standby
Using all of the power drainage values, I created a formula for calculating the estimated battery life for the roms if set to 3G, Wifi, or a mix of both. The formula uses best guess values for the number of hours spent talking, surfing, running programs, and left in standby. The breakdown is as follows: 2 hours running programs, 1 hour surfing, 1 hour calling, and 20 hours on standby.
I also did an independent test to see the effects of underclocking. Using SetCPU on Rodimus, I forced different clock speeds and ran the Long Bench Test. I also looked at what happens when you go into Standby underclocked.
The roms I tested:
Aphrodite_1.3*
RodimusROM.v1.2.3
Zefie's CM7 03012011
aospCMod 03252011
aospCMod 04032011
*I forgot to run some of the tests on Aphrodite, but that didn't effect the final calculations.
Results:
(updated 4/6/2011)
This assumes: 2 hours running programs, 1 hour surfing, 1 hour calling, and 20 hours on standby for a given day.
This chart sums up all of the testing. The CM7 roms have a hug problem when it comes to Wifi power use in the idle state. When downloading files, all the roms use approximately the same amount of power. The average 3G power use when downloading is 1600mW which is almost twice as much as Wifi, 850mW. This is in contrast to the power use when in standby with no data transferring where 3G consumes the same amount of power as airplane mode and Wifi consumes at least twice as much with Rodimus and at most 34 times as much with the CM7 roms. Rodimus and Aphrodite have much better battery life on Wifi than the CM7 roms. This all depends on how much Wifi and 3G you actually use. The transfer speeds did not effect the power consumption. Checking email which occurred at 40 kbps consumed the same instantaneous power as downloading Docs2go at full speed. This was true for both Wifi and 3G. The "Mix" results assume you spend half of the 24 hours at home using Wifi (sleeping counts), and the other half using 3G. If you would like to experiment with the constants used to calculate the estimated battery life, download the attached xls file and manipulate only the values highlighted in green. The values highlighted in pink and chart 5 will change as a result.
Update 4/6/2011: The new asop rom seems to have improved the power consumption of the Wifi antenna drastically. There is still room for improvement compared to the stock rom, but I guess that is just a trade-off for the GB features. I have uploaded an updated xls file with the new results included.
The last test involved setting different CPU speeds and seeing how they effected standby power consumption and the power consumption during the Long Bench Test of SetCPU.
As you can see, under and over-clocking has zero effect when the CPU is idle.
This chart shows that the higher the CPU speed, the more power is consumed during the CPU intensive bench test, but this does not show the entire picture. Since the bench test is using a standard set of calculations, we can compare the time it takes to finish the test across the different CPU speeds. This value is conveniently given as the result of the bench test. Multiplying the steady power consumption to the time it took to finish the bench gives us the energy consumed to finish the bench. The clock speed with the least amount of energy use is therefor the most efficient speed (for this particular phone).
When we zoom in on the results at the high end of the CPU clock speeds, we see that the highest stable clock speed for this phone, 825 MHz, is not the most efficient. It is actually 806MHz that consumes the least amount of energy to complete the test. Even though 825 is faster, the increased power consumption counteracts its speed. It is also obvious that the slower clock speeds are way more inefficient for completing a CPU intensive task.
For some reason, 320MHz and 245MHz gave identical results. I think this is a kernel or hardware bug. I tested it repeatedly and got the same results.
Conclusion:
If you want to see what your battery life would be under various conditions, download the xls file and manipulate the values in green. The values in pink will change and will automatically be plotted in chart 5. Depending on your phone habits, you can pick the rom that suits you best. Remember that these are rough estimates. Your actual mileage might vary.
Turning off Wifi when the screen is off can save you battery life IF you have no backgrounds apps that send and receive data. If you do have those types of apps, Wifi is better than 3G to leave on (not including the current CM7 Wifi issue). If you are using 3G, there is no advantage to turning it off when the phone goes into standby unless you again have background apps that consume bandwidth. 3G consumes the same amount of power as airplane mode if there is no data transferring! My suggestion is to eliminate those types of apps if you don't need them and leave 3G on. That will save you the most amount of battery out of all the mods you can do.
If you are going to use SetCPU, overclocking will save you battery life. Underclocking will actually cost you. I would recommend leaving the upper limit one notch lower than what is considered stable for your phone. The lower limit does not matter all that much. I now have my lower limit set at the same value as the upper limit. When idle, both high and low clock speeds consume the same power. When the CPU is needed, the higher clock speed is more efficient (to a point). I would advise against the "conservative" scaling that gradually changes your clock speed to task if you still decide to underclock. This will only slow you down and consume more battery power. You also don't need a separate profile for when your phone is on standby. Lower clock speeds can only worsen your battery life.
Lastly, underclocking is not the same as undervolting. Undervolting would probably decrease battery consumption, but it is not implemented in any rom/kernel for the Optimus V...yet.

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Part 3
Fixing power drain with a firewall!
Most of you probably don't believe the conclusion that 3G consumes the same power as airplane mode when idle. You've set Tasker or Juicedefender to turn off your 3G when the screen is off and have seen great battery savings. I know why...
Your installed programs are using your 3G even when the screen is off. It makes sense that you want to turn off your 3G to stop them and get better battery life, but you are punishing the wrong culprit. You may want some of your apps to occasionally update when the screen is off. You may want to use Sipdroid and get incoming calls. You may want your emails to be occasionally updated, but you don't want Google maps to constantly update the CIA to your precise location every minute. If you want to control exactly which programs have access to 3G/Wifi...
...here is what you should do:
You will need root access to do this. This will setup two script files, one to run when the screen turns off and one to run when the screen turns on. These will "enable" and "disable" the firewall. The firewall is never actually disabled. You are merely changing the rules that apply, either to give access to a limited number of apps or to allow all apps through. Because of the requirement that the scripts be executed with root access, there are actually five script files required. Two are created using Droidwall and are unique to your phone. Three scripts are attached in the zip below and are universal.
Install Root Explorer or a similar app. You can also use adb.exe, but it is up to you to figure out the correct commands.
Install Droidwall .
Figure out which apps you want to grant internet access to when your screen is off. If none, then select none.
Set the rules in Droidwall and enable the firewall.
Using Root Explorer to navigate to this folder: /data/data/com.googlecode.droidwall/app_bin/
Copy the file droidwall.sh and place it on your microSD card.
Rename it to droidwall-on.sh
Open Droidwall again, uncheck all the apps you had selected, and instead check the boxes for "(any application)". This will be the profile that is applied when you actually want to use your phone and the screen is on.
You can choose to limit access here as well, but it is safer to choose "(any application)" for now. You can come back later and recreate a more restrictive profile once you have everything working.
Apply the rules and then turn the firewall off and then back on again.
It is important that the firewall is still enabled.
Navigate back to the folder: /data/data/com.googlecode.droidwall/app_bin/
Copy the new droidwall.sh and place it on your microSD card.
Rename it to droidwall-off.sh
These two script files will "enable" and "disable" the firewall.
Use Gscript to test the scripts to make sure they work. Run droidwall-on.sh, and test an app you didn't give 3G or Wifi access to. It should be blocked from accessing the internet. Now run droidwall-off.sh. That same app should now have internet access. If this test does not work, go back and repeat the steps above. This is also the point where you check that all your critical apps function correctly with either script activated. You must make sure the scripts work as intended before proceeding. If you don't know how to add/run scripts using Gscript, learn.
While you can run these scripts as root in Gscript, running them as root when the screen turns off/on is a bit harder. The following steps have to all be done in order for the scripts to be executed correctly.
Install Tasker
Install SL4A. (more info)
Run SL4A once so that it creates the following folders on your microSD card or create them yourself: /sdcard/sl4a/scripts/
Copy droidwall-off.sh and droidwall-on.sh into the "scripts" folder.
Copy screen-off.sh and screen-on.sh from the zip file attached to this post to the "scripts" folder.
Copy "sush" from the attached zip file to the folder "/system/bin/" and set the permissions to "rwxr-xr-x".
Code:
adb remount
adb push sush /system/bin/
adb shell chmod 755 /system/bin/sush
Read here about why we need this file to run the scripts as root.
Open Tasker -> New -> Ok -> Event -> Display -> Display On -> Done -> New Task -> Ok -> + -> Misc -> Run Script
Where it says "Name" select the search button. You should see the four scripts we placed in the "/sdcard/sl4a/scripts/" folder. If not, retrace your steps to see what you did wrong. Select "screen-on.sh". Don't select the Droidwall scripts because they can't run as root as they are written.
Done -> Done
Repeat the steps to add a profile for when the screen turns off and "screen-off.sh". When you have both profiles, select Apply at the bottom.
Now when your screen is off only the programs you selected will be allowed to use your 3G or Wifi.
You no longer need to run Droidwall, but you can use it to update your droidwall-on.sh script. Don't uninstall Droidwall. If anything goes wrong and you lose all of your internet access, try deleting the scripts in the "/sdcard/sl4a/scripts/" folder, and then allowing all apps to have internet access using Droidwall.
You can actually setup any number of profiles to control your firewall using location, time of day, ...etc. To do so, create the correct ".sh" file using Droidwall. Place it inside the "/sdcard/sl4a/scripts/" folder. Then add a secondary script to run your ".sh" as root. Use "screen-on.sh" as a template to create your secondary script. Then create the proper profile inside Tasker to run the secondary script. If what I just said confuses you, don't attempt to do this. You can really mess up your phone if this is done incorrectly!
Warning 1: You are running scripts as root. This can cause all sorts of problems if the scripts are written poorly or if someone/something malicious changes your scripts. Do not try to alter the scripts unless you know what you are doing. I take no responsibility if you ruin your phone. You have been warned.
Warning 2: You can't use a droidwall-on.sh script that has been created on another phone. You must create it yourself because your apps have their own unique app number assigned to them. If you ever update a program that you gave access to, you must recreate your droidwall-on.sh file using the steps mentioned above. If you do not, your app will be blocked.
To have optimal battery life, use Wifi when the screen is on and internet usage is high, and use 3G for when the screen is off and your internet usage is mostly idle. This can be accomplished by setting the Wifi sleep policy to turn Wifi off when the screen turns off. This might be the reason it is the default setting on ALL Android phones. If you want to receive calls using sipdroid or any other voip app, create a Tasker profile that disables Wifi if you are on 3G and have an incoming voip call. And then create a second Tasker profile that re-enables Wifi when your voip call is finished. Otherwise, your incoming voip call that rings over 3G will be disconnected when you answer your phone, the screen turns on, and your phone switches to Wifi. This you can figure out how to do on your own.
I hope this helps some of you. You have a smartphone and a data plan for a reason. Use them.

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Optimizing Your Battery Life Part 4
Part 4
You may be familiar with my previous threads testing the battery life of the Optimus V:
http://forum.androidcentral.com/optimus-v/71693-optimizing-battery-drain-optimus-v.html
http://forum.androidcentral.com/opt...attery-drain-optimization-tests-part-2-a.html
http://forum.androidcentral.com/opt...es-block-apps-using-3g-wifi-save-battery.html
I had originally planned to do a 4th round of testing pitting rom vs rom, kernel vs kernel, dev vs dev, in a no holds barred match of DEATH! That wasn't going to be that hard because when I started testing this phone, there were only two custom kernels to pick from and four roms. Then some inconsiderate jerks decided to develop a bunch of kernels and roms for the Optimus V. Now we have our choice of five kernels and 15 Roms! I would have to test over 50 kernel/rom combination to cover all of the possible ones. Combine that with the fact that these kernels and roms are changing on a daily basis, and it makes my previous testing techniques impractical. I even tried to collect user data to aide in my tests, but roms where being produced faster than people were reporting their data.
So for this round of testing, I took a different approach. I decided to test the capabilities of the hardware instead of focusing on any one piece of software. Instead of getting into the details of my tests, I am going to jump to the conclusions.
Kernel Effects on Battery Life
Before I changed my testing technique, I began running tests on the five kernels that were out. I installed a rom, configured it for "optimal" battery life while still running various practical apps like sipdroid and gmail, and then ran tests on how it behaved with different kernels. My results ended up being really boring. Aside from one of the kernels that I will not name, they all performed equally well. Even the "bad" kernel has since been fixed. Then I realized what I had done. By applying my optimizations, I had equalized the playing field.
You see, you can break a kernel down into its various parts, the most important being the hardware drivers. And while you may think those would be crucial for better battery life, they are actually fairly optimized from the factory. Even though all of the kernels were compiled differently and included slightly different drivers, and the devs may add modifications to them to make them more stable or have new features, the truth is that the hardware is going to consume a minimum amount of power no matter what you do. You can probably make the drivers less efficient, but that is probably the only way you'll have the effect the battery life directly. As long as all your hardware sensors and buttons work, the kernel i doing its job.
So now lets focus on the other parts of the kernel. There is the slash screen that can be included. This doesn't really effect anything, and it too can be "optimized" and disabled by the user without changing kernels. Lastly, there are the various startup settings and scripts that are run at every boot. And while this is a necessary evil to ensure stability since the kernel loads before the rom, it is here where kernels can go wrong, wifi scan rate to be too short, setting your CPU clock speed improperly, ...etc. But whatever the kernel sets, can be un-set by the rom or yourself, and this where I nuterlized the effect of having a different kernel.
So how critical is the kernel to battery life? Not very critical at all if you are willing to configure your rom to compensate for your kernel's shortcomings.
Then how critical is the rom to battery life? Again, if you are willing to uninstall battery hungry apps, and configure your phone, the rom because just a skin.
What does effect battery life? You do, you silly goose. Turning on the screen to check for messages, having your phone auto check for emails, auto downloading angry bird updates from the Market, this is what ruins your battery life. Anything the rom and kernel do can be changed. You, on the other hand, are who you are.
Optimus V Maximum Standby Battery Life
How long can the Optimus V be left on standby? I installed a stripped down version of Aphrodite (yeah, it is possible to remove even more things). I ran my optimizations which include increasing the memory read speeds and overclocking the CPU to 806.
Side note: Some may argue that I should have put the phone on airplane mode because even though I'm not making calls, the phone checks-in with nearby phone towers. Well here is a shocker I discovered by looking at the battery draw when in airplane mode, the phone still uses its radio to (I'm guessing) check-in with nearby towers. Airplane mode has the same periodic burst of current as when not in airplane mode. That can only be explained by the phone using its radio. Just a note for all the kidnappers that are reading this, no matter what you do, if your phone is on, it will check-in with nearby towers, and you can be tracked that way. I'm sure this is for 911 purposes, but for my tests, it means that airplane mode doesn't help me.
So with the phone stripped of apps, Wifi and 3G off, and everything else optimized for efficiency, we have a standby battery life of:
110 hrs plus or minus 5 hours
I never actually went the full amount of time because this is my primary phone and my stupid/inconsiderate friends and family would insist on calling me. Get a life, losers!
The closest I got was 80 hours, but using the remaining battery to calculate the total, I averaged 110 hrs. Pretty amazing considering that my first MP3 player was the size of an alarm clock and it would play songs for 2 hours at most.
Practical Standby Time
Same setup as before, except that I left 3G or Wifi on. I also used a firewall to block all internet traffic, and I left the default rom apps installed. In this state, the phone was completely usable as a web browser, GPS device, phone...etc the whole time during the test. All you had to do was lower the firewall and you were good to go.
Standby time on 3G:
95 hours plus or minus 5 hours
Standby time on Wifi:
85 hours plus or minus 5 hours
Again, these are estimated projections, but they were fairly consistent during the testing.
Real World Use
Here I used my phone with the setup I personally use. I left all the apps the way I have them. Everything was stock mmarz. I made no calls. I left Gtalk logged in as well as a popular GV VOIP app and the actual GV app. I also had my firewall setup to block all internet traffic except: VOIP, Gtalk, GV.
I actually managed to get through the entire test and my phone, after being on a mix of 3G and Wifi, shutoff at:
74 hours!
How to Get the Most Out of Your Phone
What does this all mean? Well, for starters, this smartphone has a pretty good battery life. I think these numbers could even be improved upon, not by a new kernel or rom, but by manually configuring the settings differently from what I used. So far, I have not found the magic formula that gives you the best battery life. What I did find is that the solution does not lie with the kernel or the rom. Throughout the testing I switched the rom that I was using. That did not effect the averages one bit!
Go ahead and pick the prettiest rom you want with the features you are looking for. Then pick a compatible bug free kernel. Once you do that, only install apps that you really need. Avoid apps that have location based features as those will wake up your phone and check the GPS location on a regular basis. Also avoid apps that have advertising (just buy the pay version you cheapskate). That is wasted bandwidth and therefore wasted battery life on advertising, and who knows how often the app will update itself in the background. Finally, when you have your phone setup and configured the way you enjoy, forget everything that I wrote here. You bought the darn thing. Use it the way that you want! If you are already getting +2 days of battery life, you probably won't do any better unless you are willing to turn your phone off. If you have less than 1 day of use on a single charge, you are either a heavy user of your phone, or you have something configured incorrectly. Don't blame your rom or kernel though. In the end of day, everything can be fixed by you.

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this should be in general forum. All roms are out of date as well. This has nothing to do with android development. Just one users observations.

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dburg84 said:
this should be in general forum. All roms are out of date as well. This has nothing to do with android development. Just one users observations.
Click to expand...
Click to collapse
I'm doing these tests for the benefit of the developers as well as the end users. Part 4 is going to cover how to modify each rom to get the most out of them and compare how they perform head to head. I'm also planning on testing the performance of the different kernels I just posted. Only one of the roms is out of date and that is because the update was just released. Rest assured that I plan on testing the updated version. (new results posted in Part 2)

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mmarz said:
I'm doing these tests for the benefit of the developers as well as the end users. Part 4 is going to cover how to modify each rom to get the most out of them and compare how they perform head to head. I'm also planning on testing the performance of the different kernels I just posted. Only one of the roms is out of date and that is because the update was just released. Rest assured that I plan on testing the updated version. (new results posted in Part 2)
Click to expand...
Click to collapse
I'm not raggin on ya. I appreciate the efforts. Can tell you really put time into this.

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Nice work here. I think all android user should read this. Keep it up man. I too am on the eternal quest to keep our battery draw to a minimum. Quick question, how does your multi-meter tests compare to "Battery Monitor Widget" app's battery draw results? Are they comparable?

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I had read your thread last week because I had the Optimus and already lost it over the weekend.
I bought a cheap T-Mobile Comet and spent all of 10 minutes trying such tests at work with the Fluke 87-III. The range was only from .6uA Airplane mode 0% brightness to 2.6uA downloading over 3G.
I wonder if mine are right now. :O
Your thread (maybe it was elsewhere?) did make me realize this "50% Time Without Service" issue that I did not know of before and that airplane mode toggle after boot-up alone made the battery last so much longer on the Optimus without using any JuiceDefenders and such. It actually no longer died before returning home from work.
Thanks very much for the information. If only I still had this phone.

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ungaze said:
Nice work here. I think all android user should read this. Keep it up man. I too am on the eternal quest to keep our battery draw to a minimum. Quick question, how does your multi-meter tests compare to "Battery Monitor Widget" app's battery draw results? Are they comparable?
Click to expand...
Click to collapse
I looked into using an app at first, but all of the android apps estimate your battery usage based on the percentage reported by the OS. Even if they show a mA rating, it is estimated from the percentage reported by the OS. This isn't a very accurate way of doing it. With the multimeter, you are measuring the current as directly as possible.

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mmarz said:
I looked into using an app at first, but all of the android apps estimate your battery usage based on the percentage reported by the OS. Even if they show a mA rating, it is estimated from the percentage reported by the OS. This isn't a very accurate way of doing it. With the multimeter, you are measuring the current as directly as possible.
Click to expand...
Click to collapse
I totally agree, but for those without a multimeter(including me), using an app is the closest thing we could do to measure current draw form our devices. I was hoping on a comparison maybe on how much discrepancy we get with testing using an app compared to an actual tester.
But I won't argue on your point.
Waiting for your next tip, I'm not using 3g that much so I hope you have more for saving battery on wifi.

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Awesome
Great post.
Appreciate the effort and admire the method.
Thanks.

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Part 4 finally added! Thanks for all the support! Enjoy!

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As usual, nice insights.
with almost same configurations, my phone also can last(approximately) up to 4days in standby. Roughly an hour per hour drain(also checking the status almost every hour).

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ungaze said:
As usual, nice insights.
with almost same configurations, my phone also can last(approximately) up to 4days in standby. Roughly an hour per hour drain(also checking the status almost every hour).
Click to expand...
Click to collapse
I was hoping to get 100 hours too since I lose 1% an hour, but it turns out that the battery gauge isn't 100% correct no matter what you do to calibrate it. I'll just have to live with 72 hours.
BTW, if you are looking for an extreme mod, I think this would work on your phone too: http://forum.xda-developers.com/showthread.php?t=1072047

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Really informative! Thanks for taking the time to do this.

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I am no programmer. BUT, I know a damn good, well thought out, unbiased post when I find one(too far and few between). Great job! Thank you

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GPRS test
Could you (re)do the tests on the first page also with 2G?
I use mainly 2G, and when I want more speed I switch to 3G. Almost never WiFi (except for mobile hotspot, but that's a totally different thing). My intuition says the GPRS only uses much less power when idling than 3g (especially in areas where 3g coverage is not so good).
Could be very useful.

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wow , nice observations dude

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spaic said:
Could you (re)do the tests on the first page also with 2G?
I use mainly 2G, and when I want more speed I switch to 3G. Almost never WiFi (except for mobile hotspot, but that's a totally different thing). My intuition says the GPRS only uses much less power when idling than 3g (especially in areas where 3g coverage is not so good).
Could be very useful.
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I did a little testing of that on the side when I was running the original tests. There was no difference in power draw between the two, BUT! there could still be a real world difference.
When I tested them, they both had a strong signal available to them, but in reality you are much more likely to get a 2G signal than a 3G if you are not in a major city. In which case, a strong 2G signal will result in less effort on the part of your phone to do its business when compared to a weak (probably distant) 3G signal. When idling, if a 3G signal cannot be had, your phone will constantly look for one, but if your phone has settled to stay on 2G, then it will stay idling most of the time because it will have no problem finding a 2G tower. So while the hardware will use up the same amount of power on 2G and 3G, the availability of 2G COULD result in battery savings.
If you are in a major city with great 3G coverage and download speeds, then you'll waste battery by staying on 2G and taking longer to download the same content than you would on 3G.
As you can see, YMMV, but the tests show them as the same.