I think you really don't understand about what battery a milliampere-hour (mAh) rating is used mean .. this htc evo- 1500 mah battery is two to three day or more used advanced task killer save battery eat up.. if advanced task killer download without will take one day or less hours too short .. see Seidio Innocell 3500mAh is plenty time hours take one week or less-more used with advanced task killer .. because advance task killer applications running background on and turn off on battery prevent eat up..
Yeah, I understand about mah. I've taken Electronics class in the past. It's just that normal everyday usage or running apps that cause battery drains in real life (not just sit on the table for 2 or 3 days without using the phone). I managed to have my Samsung Moment battery last 13 hours in one charge. That's only when I dimmed the screen to 10%, turn off Email polling but one (I have 4 Email accounts), Use Onscreen keyboard instead of lighted keyboard, turn off Wifi and GPS. I even put phone on "sleep" mode everytime I put it in phone holster.
The only problem that I had issue with is that I'm outside under bright sunlight and screen was blank so I had to turn up brightness to 100% so it became readable. Other day, it's cloudy and I can read dim screen well. So everyday varies on usage and drainage on battery.
So 3,500mah Battery would enable me to leave brightness to 100% at all time and leave rest of other alone like above.
It have nothing to do with standing time, I use phone when I need it. At my work, I use it often to contact my boss or my wife ect.. Also using GPS with 12vdc automotive cell phone charger plugged in .
My point is that It have nothing to do with Advanced Task Killer saving battery drainage. I already download Advanced Task Killer and it turned off half of apps and some apps still polls for updates regardless if Advanced Task Killer turn off polling. I can't find anything to turn off that one damn polling in the running apps!! So it at least slows down the battery drain but not last 2 or 3 days with one charge!.. Mine just last 13 hours maximum if I got lucky on cloudy days.
I already returned Samsung Moment back to Sprint just day away from 30 day return policy expired and planned to get HTC Evo soon when it become available (they're sold out that's why). I did not have to pay $35 restocking fees hee hee.
Catty