[thdrdt]

This is what always bothers me in movies. There is a secret meeting. Everybody pulls out their sim because they don't want their location to be known.

Well.. no, you already revealed where you were going.

[chopin]

Even pulling out the sim wouldn't help. Without sim the phone can do emergency calls, so the phone is still connected to a network (afaik).

My paranoia is fulfilled with switching the phone off (before leaving home), but others would rely on removing the battery. Snowden recommended putting it in a fridge.