I told you a few days ago that Apple engineers contacted iPhone 4S owners to try to determine what exactly was causing the battery life issues. So far nothing has been found out about what they discovered and probably we won't find out anything either, but I have for you a method which could partially solve the battery autonomy problem in both iOS 5 and iPhone 4S. It all boils down to the GPS function and how the GPS in our terminals is used by the operating system.
In Settings>Location Services>System Services we have the possibility to choose what the GPS is used for by our iDevice. In the image above you have listed the available options and among them Setting Time Zone seems to be the one causing problems. Apparently in iOS 5 GM there would have been a bug for this option and that bug would generate problems with battery autonomy, so setting the option to OFF should solve the problem. If we are still here, I recommend that you also set to OFF: Traffic, Location-Based iAds, Diagnostics & Usage and Cell Network Search. Traffic displays information about traffic in Maps, so it is useless for us, you don't need iAds, you certainly don't want to send information about usage to Apple, the phone "picks up" a signal even without GPS and you can close the option for Compass if you don't use it in Maps application. Most of the functions there should not even be active because it will practically not reach the true meaning of the word and consumes a lot of battery.
Theoretically, setting the GPS to OFF should automatically close all these services, but I recommend that you disable them anyway, because you might notice improvements in terms of battery autonomy. I don't know if this method will completely solve the problem for the iPhone 4S because there we are talking about a high consumption even during use, but in the following days I will tell you what effect the deactivation of the functions had on my terminal.
