[HD2 Android Q&A, Help & Troubleshooting and Genera] GoCkillaz:
Ok people, you asked for it. I hope this helps!

Maximizing your Battery on your Android Device [and/or HD2]via Calibration and a little bit of common SENSE.

WARNING: DO NOT FLAME, CRITICIZE OR MAKE FUN OF SOMEONE WHO NEEDS HELP. IF ANY OF THIS GOES ON IN THIS THREAD, YOU AND YOUR POST WILL BE REPORTED. I'M SICK AND TIRED OF NERDS HAVING HISSY FITS LIKE RUDE CHILDREN. LEAVE YOUR PROBLEMS OUT OF THIS THREAD. Thanks <3

..::I AM NO WAY RESPONSIBLE FOR YOU SCREWING UP YOUR PHONE, BATTERY, OR LIFE. READ THIS CAREFULLY. FOLLOW DIRECTIONS. USE YOUR BRAIN, PEOPLE!!!::..

Intro: So, as we all know, the HD2 running NAND [and apparently, WinMo6.5] has troubles reporting REAL battery life and battery drain. This guide is for those of you who want the most out of your battery--stock or extended--doesn't matter.

This applies to all other phones running Android as well, as the steps I am giving and explaining below can be executed using Terminal Emulator.

When Should You Do This Process:

1.) Getting a New Battery [doesn't matter if it's the same voltage or not, if you put a new battery in your device, FOLLOW THIS GUIDE!!]

Why: The .bin file stored in your phone's system displays battery for one battery. Thus, if you ever change batteries, you NEED to update the .bin file, or else your phone will not display the correct battery readings--prematurely shutting off your device and/or draining battery when the phone says that you are at 50%.

2.) Switching Roms

Why: Every time you wipe your phone's system data, the .bin file gets replaced with a GENERIC file that could or could not apply to your battery. You want the .bin file to be up to date.

3.) Once a Month

Why: This should be part of a monthly routine, to get the most out of your battery. If you flash more than one rom a month, this does not apply to you, as you

should

be recalibrating your battery whenever you flash a new rom for accurate battery readings [and a potential increase in your phone's daily battery life].

What You Need:

-a rooted phone

-superuser

-busybox

-Terminal Emulator [which can be downloaded from the market]

-Set CPU [which is available to XDA members for free, can be purchased from the market as well]

-Spare Parts

-any sort of automatic task killer

-phone charger

**The method I am using involves using Terminal Emulator installed on your Android device. You can also execute this using adb commands on your computer, assuming that you know how to do it. For those of you that are inexperienced and/or want to save time, read on...

Walkthrough:

..::I AM NO WAY RESPONSIBLE FOR YOU SCREWING UP YOUR PHONE, BATTERY, OR LIFE. READ THIS CAREFULLY. FOLLOW DIRECTIONS. USE YOUR BRAIN, PEOPLE!!!::..

1.)

Plug in your device in overnight.

Your phone needs to be ON and fully functional [this especially applies to HD2 users, as MAGDLR will not reboot if phone is plugged in--it's a weird glitch]. Turn on Airplane mode if you must. [Keep it plugged in between 8 and 10 hours.]

2.)

Turn off your phone.

3.) Just in case,

plug in your phone for 10 more minutes

[just to make sure it's completely charged @ 100%.

4.)

Unplug your phone. Immediately pull out the battery, then put it back in. Press the power button. Plug your phone back in.

5.)

Open Terminal Emulator. Type in the code below.

6.)

Deplete your phone as necessary.

Once your phone automatically shuts off, turn your phone on again. Hopefully, your phone automatically shuts off as it's booting back up, or it shuts off once it brings you to your lockscreen. Repeat 2 or 3 more times.

You have now recalibrated your battery!

My Notes:

I bought a 2400mAh extended battery for my HD2, which is roughly TWICE the size of a normal HD2 battery. Yes, it is to be expected that my phone should NATURALLY last longer than stock, but read on to see the effects of recalibrating the battery.

Also, I have SET Cpu located on my SD card somewhere [I should really look for it and install it], and I am absolutely positive that if I had it installed, set with an interactive governor, the data below should be a LOT different.

Memory intensive applications

:

-Zenonia 2

-Stumbleupon

-MIUI Music

-Swiftkey Beta [along with the other modules and crap I had to download]

-Miren Browser

-Tweetdeck [2 columns set up at 15 min intervals, one at 30 mins]

-Current Widget

-XDA app [obviously XD]

Power-saving settings

:

Wifi--On [from 8am-11am]

GPS--Off

Bluetooth--Off

Normal Static Wallpaper [as in a picture, not a live wallpaper]

Brightness--0% [which is STILL too bright, but whatever]

3G--when available, I had Edge from 2:30-8:30 [which inevitably drains my battery more than 3G for some weird reason]

Auto-Task Killer

My Data:

Tested using "memory intensive applications" [see above for full list] and power-saving settings ["again, see above"]. I am running FutureShock's MIUI 2.2.1. Your results WILL vary from mine, based on what rom you are running, your phone, your battery, your running apps, etc etc etc. I am also NOT running Set CPU. I will be conducting another test soon using Set CPU, just to see what results I get. I suggest you run Set CPU, you could

potentially

double the uptime of your phone.

Time------Percent of Battery [

See notes at bottom of this chart, since a few of the percents have been changed to THIS COLOR with two ** after them

]

8:00 am ----- 100%

8:30 am ----- 80%

9:00 am ----- 98%**

9:24 am ----- 93%

10:36 am ----- 81%

10:37 am ----- 91%**

11:05 am ----- 85%

11:30 am ----- 81%

12pm [noon] ----- 81%

1:03 pm ----- 77%

2:07 pm ----- 67%

2:10 pm ----- 77%**

2:34 pm ----- 73%

3:00 pm ----- 72%

3:35 pm ----- 68%

4:01 pm ----- 64%

4:31 pm ----- 59%

5:13 pm ----- 55%

5:16 pm ----- 63%**

6:00 pm ----- 57%

6:53 pm ----- 48%

6:57 pm ----- 56%**

7:30 pm ----- 50%

8:00 pm ----- 51% ?!?!?!?!

9:45 pm ----- 38%

10:22 pm ---- 37%

Notes

Random Percent%**

This means that I removed the battery [battery pull], then rebooted the phone. Apparently, the battery readings are VERY inaccurate, being off by as much as 18%.

I have no idea why my battery went up 1% between 7:30 and 8:00. So please don't ask.

Conclusions:

Due to the fact that [apparently] my battery was being inaccurately read, random battery pulls were required to get up-to-date battery readings. I am not sure if this is an HD2 issue, or an overall Android issue when recalibrating your battery after removing the previous .bin file. IF YOU WOULD LIKE TO FURTHER THIS DISCUSSION, I WOULD LOVE MORE DATA FROM OTHER PHONES--HD2 OR NOT.

My battery is STILL running strong. Nothing incredibly drastic at all. I'm surprised that the data turned out like this.

Quick Tips:

1.) If your battery seems to be running low after clearing the stats. Check your battery's actual percent USING SPARE PARTS, then do a battery pull. See what your battery displays when you reboot.

2.) Check Spare Parts to see if your battery is being calibrated. If your battery is 3.7V, and Spare Parts says that your battery's voltage is 2.0V, then delete your battery stats again. Anything above or below .5V from your actual battery's voltage is normal error.

Q & A:

Q: I have a [insert Android phone here] running [insert ROM here]. Does this guide/walkthrough work for me?

A: YES! Go ahead! :D

Q: I typed in the code you said, and it said "Read/Write Permissions Denied". What's wrong?

A: Your phone is not rooted OR you don't have Superuser installed OR you don't have Busybox enabled.

Q: I have a question, but it's not on here!

A: Send me a PM with your question, and post it in this thread.

Q: I have data from testing this method with my phone running [insert rom here]. Can I send you the data via PM and/or post it in this thread?

A: PLEASE. The more data I receive from other users trying this out, the more accurate I can make this guide. Send me everything! :D

Q: Can I follow you on Twitter?

A: Sure. Why not. @GoCkillaz