With the launch of the new iOS 5, there were several changes, and a notable change is the optimization of battery life over older versions. And the main optimizations are completely connected only to the machine's settings.
If you have a problem with the battery, then some of the following:
1. The network settings can reduce the duration to normalize this, simply reset these settings in the application Settings> General> Reset> Reset Network Settings. Note: This also makes the device forget the passwords of Wi-Fi, forcing you to introduce them again. On the other hand, it also helps those who are not able to have the Personal Access on the iPhone 4.
2. If you do not use the new service locations, you can disable them in Settings> Serv. Location and there at the bottom (almost hidden), go to System Services. Turn off the ones you think do not use. If you do not know what, go on trial and error, turn off all switches and observe what the unit.
3. Reminders by Location (which only work on iPhone 4) are quite interesting, but spend a lot of battery, because they leave the GPS on all the time until the reminder is executed. If you do not need the function, try to avoid it.
4.The Ping is a social network that no one uses Apple. And in Brazil the function is totally useless because we do not have an iTunes Store nationwide. So, turn off this feature to prevent the device from communicating with Apple's servers for nothing. Go to Settings> General> Restrictions> Enable Restrictions> Ping.
5.Se you do not use any accessory that uses the Bluetooth, there's no reason to keep it on. Go to Settings> General> Bluetooth and turn it off.
Siri function is considered to be the highlight of the new iPhone 4S, but unfortunately is not yet adapted to our language. However, the menus are all in Portuguese, indicating that the system is prepared to receive future adaptation. Check out some screens that we did. 
