The Infinite Brief

Although people won’t be able to hear these sounds, they will contain a ‘machine recognizable’ set of Morse code-style sounds which let them tap out a message to your smartphone and order it to begin recording.

When a phone or other mobile device hears this signal, it will start capturing ambient audio, which Facebook describes as the ‘distinct and subtle sounds of a particular location created by the environment of the location, such as machinery noise, the sound of distant human movement and speech, creaks from thermal contraction, and air conditioning and plumbing noises in a household’.

The tech is built to monitor what people watch on their ‘broadcasting device’ so that the adverts they are shown on Facebook are likely to appeal to them.