Bose wireless headphones have been quietly recording and transmitting usage data via an associated app, a lawsuit alleges, without informing customers or asking them to consent to the surveillance. The app invites users to "get the most out of your headphones" by sharing their name, phone number, and email address. It then documents usage habits, the suit says, and transmits them to Segment.io, a marketing website that boasts it can "collect all your customer data and send it anywhere."

"People should be uncomfortable with it," said Christopher Dore, an attorney on the case. "People put headphones on their head because they think it's private, but they can be giving out information they don't want to share."

Though unwittingly sharing a playlist may mostly risk revelation of embarrassing taste in music, the lawsuit says more important conclusions could be gleaned from this sort of internet of things surveillance. "Indeed, one's personal audio selections — including music, radio broadcast, podcast, and lecture choices — provide an incredible amount of insight into his or her personality, behavior, political views, and personal identity," court filings note.