If you follow these tips, it will definitely make huge difference in the battery life!. It made a significant difference for me on all the devices I own irrespective of the subversions of iOS 5.
I have select push notifications on both the devices and they're connected to 3G when outside home and WiFi when at home.
Backup and restore (If possible)
Firstly, I let the iPhone discharge down to 10% battery (charge it later to 100% without disturbing) jus to calibrate it and I did "Reset Location Warnings", "Reset Network Settings" and after that "Reset All Settings"
After the welcome setup, I turned off location services for (in system services) :
1. Diagnostics and Usage
2. Location based iAds
3. Setting Time Zone
- Turned off notification sounds for some apps which are not that important.
- Decreased the brightness down to 40% coz it is favorable for me, your choice to keep it lil low. (with auto-brightness)
- Bluetooth is always off (It is turned ON by default when we do "Reset All Settings")
- Auto Lock is 1 Minute.
- Here I experimented by turning off calenders in iCloud (which made moderate difference in the standby).
- Kept push email ON only for 1 account and manually fetching the other accounts (As per your preference and priority). I have even experimented on removing and setting up email accounts once again.
- When I open the app which has location based services, it now asks me whether to allow location or not, so even here as per preference, I selected "Yes/No" as per requirement. (Permissions asked after "Reset Location Warnings")
- I also turned off location-based weather coz it constantly keeps on using location frequently and even data to keep on updating it the frequently, so moderate drain)
I also follow these tips :
1. Turn off all the background apps when not required.
2. Turned off push notifications for the apps which I don't really require.
3. Turn off iTunes Ping from Restrictions.
4. Text alerts to be kept as minimum.
5. Turn off automatic downloads (For me, it is sheer waste of bandwidth)
6. In wi-fi settings (Turn off "Ask to Join Networks") why not select it manually if you want to save enough juice for the whole day?
Now I get a sufficient battery life for more than a day and it works like a charm.