The most important and basic function is the possibility to keep the Wi-Fi module active in a locked screen (Keep WiFI on when screen times out). This is especially important because any application that uses push notifications will start using the mobile connection from your operator instead of the Wi-Fi connection – for example Skype.
The new Skype for Windows Phone 8 works in the “Always on” mode, to reduce the energy consumption, Microsoft has added the ability to choose your status visibility. If you minimize or close Skype, your status is kept on the server, not on the phone (the applications is already suspended), when you receive an incoming call or text message, it will be pushed to your phone and Skype will be re-launched automatically.
Thanks to this method, your phone uses less energy as Skype is not really running all the time, but here comes the main problem – if you lock your phone the Wi-Fi module will be stopped and all of the traffic passes through the mobile internet connection of your operator. In case you have a Skype call and accept it – everything goes through the same connection (your mobile network service).
That’s why the new Windows Phone 8 update is very important, if you are one of the proud HTC Windows Phone 8Xowners, apply the update as soon as you can!