Wearable AI: will it put our smartphones out of fashion?

Imagine it: you're on the bus or walking in the park, when you remember some important task has slipped your mind. You were meant to send an email, catch up on a meeting, or arrange to grab lunch with a friend. Without missing a beat, you simply say aloud what you've forgotten and the small device that's pinned to your chest, or resting on the bridge of your nose, sends the message, summarises the meeting, or pings your buddy a lunch invitation. The work has been taken care of, without you ever having to prod the screen of your smartphone. It's the sort of utopian convenience that a growing wave of tech companies are hoping to realise through artificial intelligence.