A homeowner's heavily connected smart home illustrates growing privacy concerns that everyday gadgets collect and potentially sell personal data, with security researchers warning consumers to change default passwords, install updates and keep devices out of bedrooms.

Julia Starzyk, 36, of Harefield, west London, controls heating, lights, security cameras, a Chinese air fryer from Lidl, dog-feeding robots and smart bulbs via her phone, while a researcher known as @log4j found that a Samsung television used an in-built microphone with automatic content recognition to track background sounds for targeted advertising.