Using cellular network data
Whenever you do anything on your phone that requires a network connection, such as send and receive email, get social networking feeds, visit websites, or download apps, your handheld device automatically connects to a cellular data network to transmit the information. If you're connected to a Wi-Fi network, the Wi-Fi network connection will be used instead.
When you do anything that requires a network connection, you may incur data charges if you exceed the data plan you have with your mobile operator. So we strongly recommend that you consider getting a data plan that meets your needs.
To change the cellular data settings on your phone:
Go to Settings > Cellular.
Tap Data connection to turn cellular data on or off.
For more information about cellular data usage, see WindowsPhone.com.
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