When I first got my iPhone 4S I noticed that my battery was draining faster than my iPhone 4 ever did. I chalked it up to having iCloud turned on as well as playing with it and using Siri. I thought that after a couple of days of me getting used to the new phone and iOS 5 features that I would let up and battery life would improve. When it didn’t improve I shut down all iCloud services (except for iCloud backups and Find My iPhone) as well as the shutting down the Setting Time Zone System Service (go to Settings > Location Services > Setting Time Zone). The battery life issue was gone for me.
This isn’t a valid fix though and Apple has released a statement about an upcoming software fix for the issue:
“A small number of customers have reported lower than expected battery life on iOS 5 devices. We have found a few bugs that are affecting battery life and we will release a software update to address those in a few weeks.”
Looks like even without Steve, Apple can be terse and too the point. Good sign and glad to see that they are paying attention.