Ensure that the device is charged completely on its first use to prolong battery life.
Reduce screen brightness to the lowest setting. See 'Setting the Screen Brightness Level'. Note: To adjust the display brightness, from the home screen select Menu > Settings > Display > Main display > Brightness
Enable Airplane Mode during limited or no cell connectivity. See 'Turn Flight Mode On or Off'. Note: To turn Airplane mode on or off, from the home screen, select Menu > Settings > Phone > Airplane mode
Turn Wi-Fi off when not in use. Note: To turn Wi-Fi on or off, from the home screen, select Menu > Wi-Fi> Options
Turn Bluetooth off when not in use. Note: To turn Bluetooth on or off, from the home screen, select Menu > Bluetooth > Options > Settings
For information about charging your battery, search tutorials for ‘Charge battery’. Note: For battery/charging accessories, visit http://www.att.com/shop/.