Imagine being able to download vast amounts of music, video clips, ringtones and much more, while waiting for the bus. All thanks to a technology called Bluetooth marketing.

The technology is not entirely new. It was used widely during the 2008 Olympic Games in Beijing, but has now been introduced in Bulgaria.

The first billboards in Bulgaria, however, do not let you download any music or videoclips just yet.
Instead, they offer the latest betting coefficients, courtesy of a large online betting company.

The first bluetooth-enabled billboards in Sofia have been installed by advertising company JT Intenvis.

Bluetooth advertising was extremely popular in public places in large European capitals, the company said in a media statement.

Bluetooth advertising, or proximity marketing as it is also called, works using a special bluetooth server, installed inside the billboard. The server constantly scans the wireless bluetooth network within a limited radius of the billboard for available devices like mobile phones and PDAs. When it finds one, it contacts the device. As the owner of the device, you will then see a message, asking you if you would like to receive an advertising message. If you opt to receive the message, the advertisement is delivered.

According to JT Inventis, 80 per cent of mobile devices sold in Bulgaria since 2000 were bluetooth enabled.

The company did not say how many of these devices have their discoverability settings set to off and will therefore be untraceable for the bluetooth-enabled billboard.

The technology has been highly controversial and was re-named bluespam by privacy advocates who consider it too invasive.