[nly]

Your phone is always reporting its position. Someone, somewhere has the capability to type your cell phone number or IMEI in to a console and find out what tower you're currently connected to. Furthermore it only takes 3 towers to trilaterate your location, and someone, somewhere has telemetry from all the towers in your neighbourhood at their fingertips.

Hell, failing that, it's been demonstrated publicly that anybody can simply purchase access to SS7 and query this sort of information to locate you, in real time, from the other side of the globe, without your knowledge. If you post your cell phone number online, many people can find you right now.

As for it not always recording, true, but you have no idea when and if it is enabled. The SIM and baseband processor are black boxes capable of running unfettered by iOS and Android. Your app preferences are simply irrelevant, and you cannot easily see or inspect the traffic going over the cellular network.

Oh, and you likely can't remove your battery.

Cell phones are an Orwellian wet dream. If you're ever doing anything you never want anyone to ever know about, whether it's illegal or just deeply private, do not take your cell phone with you.

[rdancer]

... and make sure there are no other cellphones in the vicinity