Push To Talk won't pull in the users

ARPU is the Average Revenue Per User, and it's the only reason phone companies get out of bed in the morning. In particular, it's the reason they're promoting Push To Talk (PTT), a cunning scheme that turns your phone into a walkie-talkie. It's been stunningly successful in the US, they say, and it means a whole new way of communicating with your regular correspondents. You'd really want it, if only you knew. A bit like IM for the phone, it gives you a buddy list of registered users and shows when they're available: choose one or more and press the button, and your voice either comes out of their speakers or awaits a later audition.

That much is true. What they don't say is that PTT is being seen as a way to get ARPU from a whole set of people and conditions that have previously proved resistant to cash extraction. If you're over 40, you don't text -- and that's just not good enough. The operators think that voice messaging will be more attractive to keyboard-phobic wrinklies, who'll take to it as their offspring have to texting. Likewise, if you're out and about -- driving or walking or whatever -- and can't spare enough attention to spell out the words, you can't text. The operators hope that you can at least manage a murmur, and with European pricing at around a penny for each three seconds we can therefore spend more of our time handing over money.

It's true that PTT has been successful in the US, in particular with operator Nextel -- so much so that it's trademarked the term, to the considerable annoyance of the rest of the industry. And me: PTT and Push To Talk have been commonplace terms in wireless for at least 50 years, so it's a bit like a TV manufacturer trademarking the words Colour, Brightness and Contrast. We can all take some solace from the fact that people who go in for this sort of thing generally don't do very well out of it. A long time ago, NCR set the lawyers onto anyone who described floor-standing computers as 'towers'. Our trademark, said NCR. Hands off. Ah, if only they'd spent as much time designing good computers as they did annoying people, they might have been a successful PC company.

But Nextel is a successful cellphone company, right? Well, up to a point. It's got great penetration in some markets -- construction companies especially -- and makes money, but it's not that big a company and it runs its own proprietary technology. As a result, it has a small and unexciting range of handsets - no camera phones, no smartphones - and patchy coverage, even within the US. Their GSM roaming solution? Carry two phones. If Nextel set up shop in Europe selling us what it sells the Americans, it would last as long as a Florida suntan in an English summer.

The only thing Nextel's got going for it is PTT, and that only works because of the custom network. PTT over GSM is desperately slow -- you can wait up to seven seconds for a message to be delivered -- if you do it the sensible way and parcel the voice up as packets of data. Do it the silly way, by making a phone call but disguising it as a one-way voice message, and you can get the delay down to a couple of seconds -- still nothing like a walkie-talkie. Gagging for it yet? Me neither.

Other signs are bad. You've long had the option of PTT-like services on the desktop as part of your instant messenger installation: you haven't bothered. Even real walkie-talkies have failed in the face of the GSM juggernaut -- Dolphin, the UK's public digital two-way radio system, finally died last week after being ignored for years. About the only action in the field is in thirty-quid-for-two cheapies with a range of a few hundred metres: not a revenue model to get the phone companies slavering.

The one good thing about PTT services isn't the voice, it's the buddy list. Unfortunately, there's no easy way to charge for that -- which is why the operators haven't developed it as a separate application. Doubtless many people will use the service for that alone -- or, as smartphones get better, they'll use free software that replicates the experience. If the operators are expecting much more than a passing interest in PTT, they'll have to make it truly useful -- not just a revenue-raising scheme disguised as a good idea.