A man walks down a busy high street towards a well-known coffee chain. As he gets within 500 yards of the café, his mobile phone buzzes in his pocket with an advert from the company offering him a discount on a cup of coffee.I have an iPhone. Before I got it, I had a bog-standard Ericcson.
It might sound like a scene from the science fiction film Minority Report, but personalised advertising techniques such as this are closer to becoming a reality than ever before.
I left Bluetooth on because I was driving, and forgot to turn it off as I shopped. As I got near to Debenhams, I got a text message Bluetoothed to me from their wifi advertising a sale.
That was two years ago.