Choosing Settings for Better Battery Life

To get the most battery life out of an iPad or iPhone, you can reduce the power demands in various ways-everything from dimming the screen to collecting data less frequently.

Reducing the Screen Brightness and Locking the Screen

Of all the mouths the iPad's or iPhone's battery has to feed, the screen is by far the most power-hungry-especially on the iPad. So you can improve battery life by turning down the screen brightness and setting the device to lock itself sooner rather than later.

To turn down the screen brightness, choose Settings | Brightness & Wallpaper, and then drag the Brightness slider to the left. If you choose to use the Auto-Brightness feature (by setting the Auto-Brightness switch to the On position), the device tries to automatically set a suitable brightness for the ambient lighting. You can often save more power by setting a lower brightness manually-at the risk of eye strain.

To make the iPad or iPhone lock itself sooner, choose Settings | General | Auto- Lock, and then choose a short interval on the Auto-Lock screen. The iPad offers these settings: 2 Minutes, 5 Minutes, 10 Minutes, 15 Minutes, and Never. The iPhone's settings are: 1 Minute, 2 Minutes, 3 Minutes, 4 Minutes, 5 Minutes, or Never.

Turning Off Wireless Services You're Not Using

Both Wi-Fi and 3G can chew through considerable amounts of power, so if you don't need one, the other, or both, turn them off:

• Turn off Wi-Fi Choose Settings | Wi-Fi to display the Wi-Fi Networks screen, and then move the Wi-Fi switch to the Off position.
• Turn off 3G On the iPad, choose Settings | Cellular Data to display the Cellular Data screen, and then move the Cellular Data switch to the Off position. On the iPhone, use Airplane Mode, as discussed next.
• Use Airplane Mode On the iPad or the iPhone, touch the Settings icon to display the Settings screen, and then move the Airplane Mode switch to the On position. AirPlane mode is a quick and easy way of turning off all the cellular and Wi-Fi antennas to keep the flight crew from deplaning you before your destination, but you can use it any time you value battery power over connectivity.