Battery drain after software update

I've noticed in past few days my battary seems to be suffering, I'm on an iPhone 4 iOS 4.3.2.

Normally I get through a full day with about 2/3 of the battery left, but in the last couple of days it's been much worse and my usage habits have not changed. I'm not aware of having installed any new apps or anything.

I just thought I'd post an update for anyone noticing unexpected battery drain. After reading some of the other posts here I decided to check out the Settings - General - Usage section.

By the end of the day my "Usage" was about 9 hours which I now understand to be the cumulative amount of time that the iPhone is "awake" doing thing things. As opposed to "Standby" where the phone is waiting for something to do, but not doing any significant work.

This seemed awful high because I was not making any calls or even running any games or apps for the entire day. So, I rebooted it and gave it a full charge overnight. By the end of the following day as I was about to put it back on charge as I do every night, the Usage was ~56 minutes and the battery was near full, which is my normal experience prior to recent problems.

No knowing much about the inner workings of iOS, I suspect a rogue app or process had crashed or was caught in a loop doing something stupid resulting in a high Usage time and high battery drain. This condition persisted until the reboot which obviously stopped the rogue app/process and the abnormal battery usage.

So if you're suddenly experiencing high battery drain, try a reboot as well as checking for any recently installed apps or settings changes that may have caused this.

After reading several discussions and trying everything I found this to resolve my battery drain issues:

1) Disable Ping and iTunes

2) Delete Exchange Server Email account and reinstall Exchange Server Email account

Thanks to the discussion groups!