News of a mobile that can detect bad breath will come as a relief. Halitosis is a mortifying condition, both for the sufferer, who is often unaware of it, and for his or her nearest and dearest, who have to endure it. Now those awkward interspousal conversations need no longer take place, and the nation can look forward to a drop in divorce rates, accompanied by a corresponding rise in sales of Extra Strong Mints.

But spare a thought for the poor machines. Spotting halitosis is all too easy for humans; for a phone, how- ever, it requires Nasa-style technology. All those megabytes to detect death-breath? Or as Marvin the Paranoid Android (back on air in Radio 4’s remake of The Hitchhiker’s Guide to the Galaxy) might have put it: “I've been ordered to tell you if you’ve got bad breath. Here I am, brain the size of a planet and they ask me to smell your breath. Call that job satisfaction?”

It is only a matter of time before ever more technology is condensed into ever smaller chips. Before long, handsets could not only supervise personal hygiene, but also prevent social faux pas, offer styling tips and buzz discreetly to warn of spinach between the teeth. But as any sci-fi fan knows, all technology, however benign to begin with, has its risks. Imagine a Blade Runner scenario, in which mobiles, bored of their menial status, rebel, stage organised “phone-ins” and drive their human oppressors mad with non-stop ringtone renditions of Blondie’s Hanging on the Telephone. When it comes to technology that talks back, it’s enough to make one nostalgic for that old psycho computer HAL: he may not have liked being switched off either, but at least was softly spoken.