iPhone: The Missing Manual, 2nd Edition

Airplane Mode and Wi-Fi Off Mode

To save even more battery power, and (on a plane) to comply with flight regulations, you can turn off all three of the iPhone's network connections in one fell swoop. You can also turn off Wi-Fi alone.

• To turn all radios off. When you turn on Airplane mode (tap Settings, and then turn on Airplane Mode), you turn off both the Wi-Fi and the cellular circuitry. Now you can't make calls or get onto the Internet. You're saving battery power, however, and also complying with flight regulations that ban cellphones in flight.

  

• To turn Wi-Fi on or off. From the Home screen, tap Settings→ Wi-Fi. Tap the On/Off switch to shut this radio down (or turn it back on).

  Tip

  Once you've turned on Airplane mode, you can actually tap Wi-Fi and turn that feature back on again. Why on earth? Because a few airlines are offering Wi-Fi Internet connections on selected flights. You'll need a way to turn Wi-Fi on, but your cellular circuitry off.

• Once you're in Airplane mode, anything you do that requires voice or Internet access—text messages, Web, email, Weather, Maps, and so on—triggers a message. "Turn off Airplane mode or use Wi-Fi to access data." Tap either OK (to back out of your decision) or Settings (to turn off Airplane mode, turn on the antennas, and get online).

You can, however, enjoy all the other iPhone features: use its iPod features, work with the camera and photos, ...