iPhone 4S battery problem fix: how to get more than a day's life on a single charge

how I got more than 7 days (estimated) 3.5 days (with actual light usage) of standby time on my iPhone 4S (see image 1) in 3 simple steps (by turning off email fetching):

step 1) Settings > General > Reset > Reset All Settings (see image 2, and this won't wipe out your phone, just resets your iOS5 settings)
step 2) Settings > Mail, Contacts, Calendar > Fetch New Data > Push to Off, Fetch to Manually (see image 3)
step 3) Settings > Location Services > System Services > Setting Time Zone to Off (see image 4)
step 4) optional: Settings > Notifications > Calendar > Notification Center to Off

If this still didn't work for you, try deleting all of your email accounts, reboot the phone, and add each one back.

The tradeoff here is that I won't get notified about "You've Got Mail!", but that's about as useful to me as a dead phone, so for me it's well worth the gain battery life.

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Edit: The original credit for this technique goes to Christopher Breen at MacWorld, who attributed the "Reset All Settings" hint to John Gruber. I was hesitant to try it at first, but turns out it's not a factory reset but more a preferences reset that preserved all of my data. http://www.macworld.com/article/163200/2011/10/troubleshoot_iphone4s_battery.html