Re: Sensors and transponders better than cameras?
And the Government are probably already considering it
If you carry a mobile phone you are already doing everything you fear. They know whose phone it is, where it is, where it's been. It's quite likely they can use it to bug you. Even if you try to conceal your ownership of it, they can still cross-reference it to everyone you ever called with it and find out who you are with a minimum of further interrogation of their records.
A transponder could be far more anonymous than a phone (and cheapest possible would not be personalized).