The feature is an optional one, something the company emphasizes in its announcement. The tech giant does seem well-aware that in these days of Snowden surveillance revelations, people might not be too keen for Facebook to take control of their smartphone’s mic and start listening in on them by default. It’s only rolling out the feature in the U.S. and a product PR person emphasized repeatedly that no recording is being stored, only “code.” “We’re not recording audio or sound and sending it to Facebook or its servers,” says Facebook spokesperson Momo Zhou. “We turn the audio it hears into a code — code that is not reversible into audio — and then we match it against a database of code.”"
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