That IPhone and Samsung with a non replaceable battery is...a mic and camera that is always on. Potentially even when the device is off.
Microphone jamming apps (like PilferShush Jammer) and electrical tape exist, at least.
Most of the devices have a switch for the microphone that is supposedly implemented in hardware rather than software. And the vast majority of smart home devices do not have cameras.
Granted, the ease of use of their functionality is largely dependent on the microphone being on at all times.