If you spend your time, like I do, reading up on developments in the magical world of mobile, then you've probably come across the term "bluejacking": it's the practice of using your Bluetooth-enabled phone to send a message to another handset, and works by embedding your message into an entry from your address book. Remember how it's easy to beam entries from your address-book to your friends using infrared on Nokia phones? It's a very similar thing, but more often used to send messages to random strangers who happen to be near you.

Bluejacking is getting a lot of press. It's sometimes described as a craze, we're given the impression that it's on the point of becoming widespread, and the name itself makes the practice sound more like a dangerous subversion of other peoples phones than the vaguely annoying and rude prank that it is.

This has the whiff of hype to me, but worryingly, a number of people who I like and respect seem to believe that it is something special. So I've been wanting to post my thinking on bluejacking for a few weeks now. Here goes...

Why does this matter? Why is it useful to be able to send short messages to people you don't know, who happen to be within 10 metres or so (Bluetooth's range) of you? I can understand the novelty value of playing a prank on someone, but once that wears off, what does bluejacking actually offer? Comparisons with SMS don't hold up, for me: SMS lets you quickly and cheaply interrupt someone and get a message to them whilst bypassing social conventions and small-talk, and it's something you use in a very informal fashion to communicate (principally) with people you already know well.

This is not to deny that there will be interesting applications built around Bluetooth; in fact some are emerging already. But bluejacking won't be one of them.

Who can bluejack, and who can be bluejacked? What's the potential audience for this practice? Bluetooth-enabled phones are typically those marketed at business users: hardly a good fit with the teen demographic you'd expect to be driving this new "craze". And in order to be bluejacked, your handset needs to have Bluetooth activated and be marked as "discoverable", so that you can be seen by other devices in the locality. Many phones don't, by default, meet either of these requirements. So the audience is small.

Who's doing it? I've been trying to get an idea for how prevalent this practice is, and I'm going to conduct a few experiments this week to see if I can find out (which will involve leaving temptingly discoverable handsets lying around in prime bluejacking locations and seeing if anyone finds them). The only research I've seen is by a PR company with a vested interest in promoting bluejacking, and it beggars belief that 85% of the population know about this stuff. And the conclusion that "68 per cent would welcome the opportunity to receive targeted promotional messages or electronic coupons, but only on an opt-in basis" is completely unrelated to bluejacking (which is all about messaging people who neither know you nor have your permission to contact you in a rather underhand way).

So, who's bluejacking? As far as I can see, it's a few folks on the BluejackQ and Esato message-boards, plus industry folks with an interest in whizzy new stuff giving it a whirl (and there does seem to be an overlap between these two categories). This isn't a widespread practice, beyond the initial novelty value it lacks any worthwhile use that will make it a widespread practice, and anyone who tells you otherwise is at best following a hunch.

As anyone who's regularly read this site knows, I'm bullish about mobile: I think it is changing our lives and the society we live in, and will continue to do so in new and unforeseen ways. But jumping on every prank which new mobile technologies enable and declaring it important, without any evidence or research to back this up, only cheapens the really interesting and valuable work that's being done in this field.