Warren Buffett has traded his flip phone for an iPhone, and says Apple is 'probably the best business I know in the world'

· *Warren Buffett told CNBC's Becky Quick in a Monday television interview that Apple is "probably the best business I know in the world."*
· *The "Oracle of Omaha" also said that he has finally traded in his old flip phone for an iPhone. *
· *He called the smartphone an "incredibly useful product to people that grows more...