Mobile device power saving

A method is provided for power saving in a mobile device ( 10 ) for use in conjunction with a plurality of beacon devices ( 12, 14, 20 ), together with devices for use in such systems. The mobile device detects and receives data from such beacon devices including a first one of said beacon devices when the mobile device is at a first location within a first predetermined distance from said first one of said beacon devices. The mobile device is equipped to detect movement thereof and, having detected the first one of said beacon devices, the mobile device is disabled from detecting such beacon devices until said device has determined that it has moved from said first location.