silent

I see sign saying to switch off my mobile phone at cinema theatre, public events, social gathering, hospitals, flights, temples and many other places.

Reason for their suggestion is:
a) mobile waves can create interference to other electronic eqipments
b) distract people from their current activity.

In first case it is essential to switch off or jam signals, in second case taking mobile into silent mode is sufficient.

But even if I have intension to shift my mobile into silent mode or switch off, I tend to forget about it.

I was thinking about it a while and come up with a idea which can be used to take mobiles to silent mode or entirely switch off.