I’ve visited Australia as a traveler, apparently I’ve heard that “burner” phones over there are not really anonymous since they literally demand for ID (WTF? That defeats the purpose of it being classed a burner phone) otherwise they aren’t allowed to sell it to you, what’s meant to be a ‘disposable’ phone turns out on buying a regular one when you consider the fact they ask for driver’s license prior to finalizing the transaction.
Don’t even talk about SIM cards for BP, since that too is subjected to KYC in Australia as I’ve learned. They want to harvest data such as driver’s license & residential address (for citizens), or passport info / flight confirmation (return ticket) if you’re a traveler. Without those things: vendors can’t legally sell you a burner phone, so: DON’T BUY A BURNER PHONE IN AUSTRALIA. Their method of acquisition defeats anonymity.


Police have successfully identified burner phones by looking at what other phones they’re geographically close to. What I mean is, some crime boss carried his burner and regular phone around together all the time, so the phone records showed that the anonymous burner phone used to make shady deals was always near Joey Mobster’s phone. Hence, Joey is the likely owner of the anonymous burner.
If you do get a burner, never turn it on near your house, near your work, or near your regular phone. Keep it off and wrapped in aluminum foil until you’re in a location that you can’t easily be connected to.
Does aluminum foil actually work? You might be better off using a faraday bag that designed for this purpose.
It’s probably not as good, but this where convenience wins because it’s good enough. You can get aluminum foil almost anywhere and it’s already in about every house.
It may not be as effective as a proper faraday bag but yes it can greatly reduce the signal coming in/going out
Depending on the bag, foil works better. Always test your gear before relying on it.