By Stephen NellisJan 29 (Reuters) - Apple beat Wall Street estimates for quarterly revenue on Thursday, powered by strong demand for its iPhones and a sharp rebound in China, with CEO Tim Cook telling Reuters that demand for the latest handsets was "staggering." Apple's iPhone 17 ​lineup helped lift sales across key markets, easing investor concerns about a hardware sales plateau. IPhone revenue rose to $85.27 billion in the fiscal first quarter ended December 27, well above the $78.65 billion analysts had expected. Apple said iPhone sales set records in every geographic segment, highlighting broad-based demand despite macroeconomic uncertainty. The iPhone maker posted quarterly revenue of $143.8 billion, up 16% from a year earlier, topping analysts' average estimate of $138.48 billion, ⁠according to LSEG.