Avi Schiffmann is an entrepreneur with a crazy idea that might become our new reality. After being on a podcast, he wondered about how he had presented himself. Instead of asking a human being for feedback, he asked a pendant he had been wearing around his neck during the recording. It told him he needed to be a better listener.

The round plastic bauble known as Tab, the main product of Schiffmann’s wearable artificial intelligence startup, had a tiny microphone that fed a real-time audio recording of his daily interactions to an AI model. Tab had some tips. "You ... abruptly changed the conversation topic,” the device replied via text to his phone. If Schiffmann had acknowledged something his interviewer said, that "would have made you appear more thoughtful.”

Tab goes on sale next year for $600. A rival called Rewind will sell a similar pendant for $59. Tech giants are also exploring these products.