New Delhi, April 14 -- WHEN LAURENE POWELL JOBS during a recent interview asked Sam Altman and Sir Jony Ive about the artificial-intelligence "thing" they were working on, both men were coy. But Mr Altman, OpenAI's boss, did suggest that using the new device would feel different to the all-consuming iPhone created by Sir Jony and Ms Powell Jobs's late husband. He likened the experience of a smartphone to walking through Times Square, with its flashing lights and loud noises. Mr Altman and Sir Jony are not alone in working on an alternative. The race to unseat the smartphone is on.

Over the past two decades the iPhone and its imitators have come to dominate how consumers interact with the digital world. The result has been one of the most...