The battery drain issue for ios 6.1.2 even after reset all settings .......my drainig issue got fixed after the following steps
1. Reset seetings-factory reset
2. Delete all mail accounts
3. Set automatically -off(explained below)
4. Location services-off.
The battery drain on iPhone 3gs or later is because of auto time zone under date & time in settings tab. If your location services are turned off, it would still search for time zone. Please turn off the set automatically under the settings General-Date & Time-Set Automatically-OFF
Apple, you effectively BRICKED my iPhone!
Before the "upgrade", I got about 4 days of time in stand-by (no usage whatsoever, WiFi/bluetooth/screen etc off).
After the "upgrade", I got about 16 hours of time in stand-by (no usage whatsoever, WiFi/bluetooth/screen etc off).
(I have tried all kinds of "solutions" and minimum configurations one can find on the net - nothing fixes any of this.)
I know you have an interest in devaluating your customers' phones: You want them to buy new ones. Guess what: THIS IS NOT GOING TO HAPPEN, YOU WILL NOT GET AWAY WITH SUCH FRAUDULENT BEHAVIOR!
You will never get 1 cent from me again.
I also will make sure ALL of my family and friends (including on Facebook, Twitter, LinkedIn) hear about what you are doing.