NOBODY likes a visit to the doctor's surgery — but we'd miss it if it was gone.

The growth of medical apps available for smartphones and tablets has already led some commentators to imagine a dystopian future in which no one ever gets to see a doctor — a world in which people just tap their symptoms into a faceless computer and wait for the diagnosis.

Medical apps are big — there are now 97,000 available, and research by Research2Guidance predicts the worldwide health app market will be worth $26 billion by 2017 and half the world's smartphone users will have downloaded health apps.

Health app usage is a bit like drug addiction — you start with something innocuous like a running or calorie counting app, then progress to heart rate and sleep patter monitors, and before long you're calculating glomerular filtration rates and diagnosing yourself with epidermodysplasia verruciformis.

Anyone who has used NHS Direct online will be familiar with the dangers of trying to diagnose themselves using the internet.

Tap in a few symptoms — mild headache and sore throat — and suddenly you've convinced yourself you're at death's door and there's a huge red box on the screen telling you to dial 999.

The shock is enough to give anyone a heart attack.

For those who want to put themselves through this kind of misery, WebMD is one of the most popular self-diagnosis apps, while those of us in good old Blighty can use NHS Direct's NHS Health and Symptoms app.

Other fun (and not so fun) apps include fertility monitoring, mood and depression indicators, and even some that analyse blood sugar levels.

There are also many apps intended for use by healthcare professionals, serving in place of reference books giving access to information about drugs, medical news and so on. Medscape and Epocrates are the most popular. But if I was lying stricken in a hospital bed and, in response to questioning, my doctor pulled out his phone, I'd be a little concerned.

The only advantage I can see in a future in which smartphone apps replace doctors is that we'll no longer have to deal with annoying medical secretaries.

At least Google Play Market isn't patronising, rude and obstructive when you try to download WebMD.

Anyway, I think I need to go and have a lie down now. All this nightmare-future-imagining has given me a headache.