If you are using a smartphone with apps installed, some of the apps might be using
the Internet connection to update weather information, Facebook news, automatic
email download etc. This traffic will be charges based on your Internet price plan.
If you want to avoid any Internet sessions running in the background, you can adjust
the setting for each App manually, or disable mobile Internet on your smartphone,
which can be done from Settings menu. You can also disable mobile Internet by sending
an SMS free of charge to 500 with ‘internet off’. If you wish to re-enable
mobile Internet, send an SMS to 500 with ‘internet on’. You might have
to restart your handset for the changes to take effect.