Beacons - a new marketing ploy or big brother with bells and whistles?
Google is getting in on the beacons act. Beacons, if you don't know, are small devices that use Bluetooth to send signals to smartphones based on proximity.
Last year, Business Insider predicted that there would be five million of the things in use by 2018 - and of those, four million will be used in retail outlets.
They were installed on London's Regent Street as part of a £1.7m (€2.4m) upgrade to push marketing messages to shoppers. In the USA, the bigger baseball teams use them to help fans find their seats. And Virgin Atlantic used beacons to tell passengers to open their electronic boarding pass when they approached airport security.