Many people are complaining that their iPhone batteries are draining too fast after they installed iOS 6. Check out this thread in the Apple Support Communities for a long discussion on the causes and the remedies. The most common complaint is that after a full night of charging the battery to 100%, it drops to 75% or so within an hour with little or no usage. Although this is perceived to be a common issue, it’s been noted that there are similar complaints each time a software update has been issued by Apple.
No matter the cause, it’s extremely frustrating to have an iPhone battery that dies quickly after a full charge. One remedy is to calibrate your iPhone’s battery. This should only be done after you’ve tried the following: resetting your network settings; turning off Bluetooth when not in use; disabling notifications, iCloud, location services, and usage reports. These settings are easy to adjust and should help retain your iPhone’s battery life.