That's why a modular mobile phone is so interesting.

The important aspect of a modular mobile phone is not what you can add to it (silly little consumer modules) but what you ca subtract from it.

With a modular mobile phone, you could physically isolate the GPS/GSM/LTE/bluetooth components at will.

My prediction is that the google modular phone, whatever it's called, will have the cellular components on the base system and not removable, which is a pity.

Most electronic cards have built in batteries like the CMOS battery in computers. So just removing the battery or pulling the cord will not be enough to "turn it off".

See <https://www.paraben.com/stronghold-bags.html>.

> Paraben's StrongHold bags block out wireless signals from cell towers, wireless networks, and other signal sources to protect evidence.

Works both ways :)

I thought Faraday cages had to be powered to block EM waves...

Try putting your phone in a metal box like this: http://www.containerstore.com/shop?productId=10031018&N=&Ntt...