Privacy expert reveals why she only keeps Alexa downstairs 

Gadget fans who worry about their smart speakers eavesdropping have been urged to banish Alexa from the bedroom.

Dr Hannah Fry, the first female mathematician to deliver Christmas lectures from the Royal Institution, has revealed she keeps Amazon’s voice-activated assistant in downstairs rooms only.

Dr Fry, 35, says families should consider similar limits on which rooms the devices are kept in.

Her advice follows revelations that Amazon has eavesdropped on homes across Britain. Whistleblowers said earlier this year that people working for Amazon had tapped into conversations through Alexa speakers to check the devices work, picking up moments such as a woman singing in the shower and bank details being read out.

It is estimated that more than two million UK households own Alexa devices. Dr Fry, an expert on tech company algorithms, says there is a slow ‘creep’ of allowing the gadgets – and similar ones from Apple and Google – to invade our privacy.

Amazon’s voice-activated assistant activated by a trigger word [such as “Alexa”]

The associate professor at University College London said: ‘I think there are some spaces in your home, like the bedroom and bathroom, which should remain completely private.

‘This technology is activated by a trigger word [such as “Alexa”] but it keeps recording for a short period afterwards. People accept that, but we should all spend more time thinking about what it means for us.’ Amazon has repeatedly denied that its gadgets are spying on people, but earlier this year insiders told Bloomberg that scores of workers based in Costa Rica, India, Romania or the US could each hear as many as 1,000 audio clips a day.

After asking tech firms to provide the data they had collected on her, Dr Fry found recordings of everyday conversations within her home.

She said: ‘There are people who are very senior in the tech world who will not have so much as a smartphone in their bedroom.

‘If a company is offering you a device with an internet-connected microphone at a low price, you have to think about that very carefully.

‘I have both an Alexa and a Google voice-activated device and I regularly turn them both off. People really must set their own limits.’

Dr Fry’s Christmas Lectures will examine our changing attitudes towards privacy, as well as how to avoid the distractions of the digital sphere. They will be shown on BBC Four on Boxing Day, December 27 and 28.