Phones in meetings have sparked an unexpected corporate debate that's dividing two of the world's most influential CEOs. People should be fully engaged and avoid checking devices during meetings, JPMorgan Chase & Co. (NYSE:JPM) CEO Jamie Dimon said. Speaking at the Fortune Most Powerful Women summit in October, he added that focus and presence are non-negotiable in the boardroom. International Business Machines Corporation (NYSE:IBM) chairman and CEO Arvind Krishna, however, sees it differently. He said ...