A stolen iPhone or any phone can be made untraceable with simple aluminum foil. In this video, team Tech360 tests how thieves use this 'Faraday cage' trick to block Apple's 'FindMy' features before shipping off stolen devices to other countries. By wrapping a stolen iPhone in a few layers of foil, they are instantly able to block all cellular, Wi-Fi, and GPS signals. The phone immediately goes offline, disappearing from the Find My grid, giving them all the time they need to crack it or sell it for parts.