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 phone 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
is used instead.
Depending on your mobile operator, your Wi-Fi may turn off when your screen times out. If you set Wi-Fi to stay on, then your phone can then use a Wi-Fi connection even when the screen is off. This uses battery power, though, so your battery life can be shorter compared to when Wi-Fi turns off when the screen times out.
This tutorial will show you how to turn on or off to keep Wi-Fi on when the screen times out
on your Windows Phone 8