Bluejacking is the sending of unsolicited messages over Bluetooth to Bluetooth-enabled devices such as mobile phones, PDAs or laptop computers, sending a vCard which typically contains a message in the name field to another bluetooth enabled device via the OBEX protocol.

Bluetooth has a very limited range, usually around 10 metres on mobile phones, but laptops can reach up to 100 metres with powerful transmitters.

The name originated with a user named ajack on esato.com. Jack was in a bank, searching for other BT enabled devices. When he found a Nokia 7650, he sent the owner a message saying "Buy Ericsson". He called it bluejacking, and it stuck ever since.

Some people think that the term bluejacking comes from Bluetooth and hijacking. While that certainly sounds logical, a bluejacker doesn't hijack anything: he merely uses a feature on his and the recipient's device. Both parties remain in absolute control over their devices, and a bluejacker will not be able to take over your phone or steal your personal information.

Bluejacking is quite harmless, but because bluejacked people don't know what is happening, they think their phone is malfunctioning. Usually, a bluejacker will only send a text message, but with modern phones it's possible to send images or sounds as well.

But with the increase in the availability of bluetooth enabled devices, these devices have become vulnerable to virus attacks and even complete take over of devices through a trojan horse program.

External links

• Esato, The SonyEricsson community site where Bluejacking was "discovered"
• bluejackQ, "First" website dedicated to bluejacking
• MobiLuck, The First Bluejacking software for Smartphones