Apple iPhone 4G - Manual (Page 74)

You can also turn off cellular data to prevent any cellular data usage.
Turn off Cellular Data: In Settings, choose General > Network, then tap the Cellular
Data switch to turn it off.
Set iPhone to add the correct prefix when dialing from another country: In Settings,
tap Phone, then turn International Assist on. This lets you make calls to your home
country using the numbers in your contacts and favorites, without having to add a
prefix or your country code. International Assist works for U.S. telephone numbers only.
When you make a call using International Assist, “International Assist” appears on the
iPhone screen, alternating with the “calling …” message, until your call is connected.
Note: International Assist may not be available in all areas.
Set the carrier to use: In Settings, tap Carrier, then select the carrier you prefer. This
option is available only when you’re traveling outside your carrier’s network. You can
make calls only on carriers that have roaming agreements with your iPhone service
provider. For more information, see “Carrier” on page 190.
Get voicemail when visual voicemail isn’t available: Dial your own number (on a
CDMA model, dial your number followed by #), or touch and hold “1” on the numeric
keypad.
You can use Airplane Mode to turn off cellular services and then turn Wi-Fi on to get
access to the Internet, while preventing voice roaming charges.
Use airplane mode to turn off cellular services: In Settings, tap Airplane Mode to turn
it on, then tap Wi-Fi and turn Wi-Fi on. See “Airplane Mode” on page 187.
Incoming phone calls are sent to voicemail. To make and receive calls again and get
your voicemail messages, turn airplane mode off.
74 Chapter 5 Phone