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Is your iPhone hot as hell? Do you hear buzzing from your speaker constantly? then, you need to turn PUSH NOTIFICATION OFF. If you can't see in Settings, install Push enabled app like TapTap2 and turn it off. It helps alot. When I had push notification on, I could literally watch my battery % goes down like 1% per minute. It's insane!
 
RE: OS 3.0 Battery Drain

So, rebooting doesn’t do the trick but watching your wireless connectivity does. If you are in a weak cellular or WiFi area, move to a better coverage area for a while. It takes a bit of quiescence for the iPhone to figure out what is the working SSID, cell network (3G or Edge).

-RJ
 
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