17 of 27Image
Switch from 'push' to 'fetch' email
Push email is very useful for when you're running against the clock. Emails are downloaded automatically and instantly from the server when they arrive, rather than waiting for you to send and receive. But if you don't mind waiting that long, you can reduce the download cycle so your iPhone isn't constantly listening for new email. Instead, it will run a schedule every few minutes, which ultimately helps in conserving the battery life.
Go to Settings > Mail, Contacts, Calendar, then scroll down to Fetch New Data. From here, disable the Push option. After this, scroll down and set the fetch schedule to Every 15 minutes so that it runs the "send and receive" schedule every quarter-hour. If you need certain email accounts to push email to your device, select Advanced and confirm the setting for each separate account.
Enable Wi-Fi while you're at work or home
Wi-Fi and other wireless radios should be disabled when they're not being used, as they use a significant amount of battery life. If you are at work or at home, and you're in a building where cellular signal is weak — such as a thick-walled house or a city apartment — you might find that leaving Wi-Fi turned on and connected to a stable network helps your battery throughout the day.
Anecdotal reports suggest that when your iPhone has good cellular signal, the device's battery will remain at a relatively stable discharge rate. But when you're on an older GPRS, EDGE, or 3G, your iPhone's battery life may decrease far quicker because it is constantly searching and "pinging" for a higher-quality cell site with better signal.
Under the swipe-up Control Center, tap the Wi-Fi button (second in from the left) on. Or, go to Settings > Wi-Fi, and set to On. Also, set Ask to Join Networks to Off to keep that Wi-Fi network connected.
Switch off Wi-Fi, Bluetooth when you're out and about
If you are not near or not using a Wi-Fi hotspot, or sending items to other devices using Bluetooth, these can (and should) be turned off.
Under the swipe-up Control Center, tap the Wi-Fi button (second in from the left) off, and the Bluetooth button (middle) also off.