Turn your mobile phones off when shopping or be tracked.

[Reality Jones]

I worked on the Cabot circus in Bristol when it was being built. I had to do some work in their security room deep within the complex. It was like being in a NASA control room, over three hundred cameras covering every inch of the shopping centre (including the hidden ones in the toilets)
What more could they possibly learn by tracking your mobile movements?
I have a smart phone and many of the apps that are dowloaded stop your phone from 'sleeping' which means it can be tracked at all times even when apparently switched off.
We are in a Big Brother world already but unlike the book or the film, he is not so obvious