Apple is currently investigating reported battery life problems experienced by iPhone 4S users. There are many tips and tricks floating around about how to extent battery life on your iPhone, but you shouldn't have to shut down most of the useful functions of your device to get battery life back. Normally these problems are due to specific bugs or corrupted files in the iPhone firmware or applications (this happened with the iPhone 4.1 update).
iPhone 4S battery life improvements
Apple will often issue a fix in the next iOS update, however in the meantime iPhone users must do what they can to solve the problem or deal with abbreviated battery time. There are many general tips and tricks that can improve battery life on your iPhone, but these involve much compromise and will switch off many features of your iPhone. In the past specific apps such as Ping and Game Center were pegged as culprits. The flood of feedback from users of the iPhone 4S point to these top 5 fixes for short iPhone 4S battery life:
1. Location Services Time Zone Bug
Navigate to Settings -> Location Services -> System Services -> Setting Time Zone -> OFF. This feature has been reported to be constantly accessing the iPhone 4S location without reason, checking the time zone and draining the battery. If you're not traveling you will not miss this feature.
2. iCloud Syncing Problem
Users have reported that iCloud can mistakenly fall into an updating loop and constantly try to sync data to remote servers. This will absolutely kill battery life in short order. The problem may be related to corrupt backup files, or corrupted Contacts. You can turn off iCloud contact syncing by navigating to Settings -> iCloud. If this doesn't help, you can turn OFF or delete your iCloud account. To fix the problem and use all of the features of iCloud restore with step 5.
3. Siri's Raise to Speak Feature
Under Settings -> General -> Siri you can turn off the Raise to Speak feature. It's possible the accelerometer is draining the battery and the problem is related to this function. Sure, it's a drag to have to press the home button, but it's even worse when you go to use Siri and the iPhone is dead.
4. Location-based Reminders
Overuse of the Reminders app can be helpful but very detrimental to the battery in the iPhone 4S. Especially when the reminders are location-based. This can cause the iPhone to constantly check the GPS location of the iPhone to determine when it should trigger the reminder. It's just a fact that grabbing a signal from satellites in space on a constant basis will drain your battery. Depending more on your biological memory will save that battery.
5. Restore the iPhone 4S as a New Phone
This is the step that everyone dreads, as you will lose your settings (mail, preferences, etc.) but sometimes it's the only way to solve a difficult problem. Apple normally insists you try to restore with iTunes before they will service a problem or replace a device. Make sure to back up your iPhone first, transfer purchased content to your computer, and when restoring choose Set up as a new phone (not Restore from backup). Battery problems caused by corrupted files or other issues can often be fixed with a clean restore of the iPhone.