San Francisco: Apple on Thursday said it saw record-high earnings in the final three months of last year, with iPhone sales surging in greater China. The tech giant reported profit of $42.1 billion on revenue of $143.8 billion in the recently-ended quarter. The iPhone "had its best-ever quarter driven by unprecedented demand," chief executive Tim Cook said on an earnings call. Sales of iPhones grew around the world, climbing to $25.5 billion in the crucial Greater China market as compared to $18.5 billion during the same period a year earlier, according to Apple. The number of Apple devices in use around the world has topped 2.5 billion, Apple reported.