Nissan's solution for distracting smartphones is called Signal Shield. At its simplest, it's a Faraday cage built inside a Juke's armrest, and when you place your smartphone in the compartment and close the lid, any cellular, Bluetooth or wifi electromagnetic signals are blocked. It's not exactly groundbreaking technology as it was first invented in the 1830s, but it's effective. And when the lid is opened, the phone will resume working normally. Music stored on the phone can still be accessed via USB connection, so it's not completely bricked by the trick armrest.
The Signal Shield is still a one-off concept, but it makes sense – if turning the phone off or selecting flight mode is a move too far. Then, of course, there is the option of using a couple-year-old smartphone with such a weak battery life that it'll give up the ghost immediately after disconnecting from its charger.