Not all people have Moblie Phones, it's the same with cars not all people drive Cars, I don't own a car and yet if I want to go somewhere I have to get a lift from one of the memebers of the wee group I'm in, and what happens when I phone up to find a place, the person on the other phone (home for me) because I hardly ever use my moblie phone, and what is the use of having a mobile phone in your house when you have a 'landline' why can't you use that, saves money and time, but as for the car I get told how to get to the place and the person on the other phone thinks that I have a car, and then when I tell them, they become cofused, because they don't use the bus/train. so they can't give you directions.
So please Mr Harding don't asume that everyone that listens to your programme has a phone/computer.
I can go on all day/night.