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I used to have battery life drop like this during standby for long periods. I turned off cellular data and viola battery life was amazing. Phone uses too much power to keep that signal. You don't even need cell data to text or call so not much point keeping it from sucking battery. I turn on cell data now only when i need it, and i get over 9 hours in usage.

can you still receive MMS' with cell data turned off?
 
http://apt.saurik.com/debs/

SSH into ur phone, Place the .Deb in tmp folder and use ifile or Mobile terminal to install.I would recomend uninstalling Mobile Substrate first but this will uninstall all ur JB apps.
I just installed the deb over the current version & it seems ok tho.
SORRY, Too many tabs open wrong thread. haha
 
My battery life was excellent with OS 4.0, but as soon as I updated to 4.01, I noticed that the battery life went down much quicker....maybe 25% faster. I made no changes to the iPhone4, nor different usage.

This is when I noticed a big change in battery life.

If it keeps up, I think I'll wait until after september 30 and take it to apple for a replacement.
 
I just wanted to update everyone. After this latest release, 4.0.2 which held the security updates, I seem to be getting awesome battery life again.
 
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