Apple reclaimed the throne as the world's top smartphone seller for the first time in five years on Tuesday, beating out rival Samsung in units shipped for the holiday quarter and boosting revenues with a strong showing for its new, top-of-the-line iPhone 7 Plus.
The iPhone sales numbers, and a profit of almost $18 billion, both handily beat Wall Street expectations, sending its shares up 3 percent in after-hours trading.
But the gains were tempered by Apple's cautious outlook for the current quarter, which it mainly attributed to the strong US dollar, which hurts companies like Apple that sell a majority of their products overseas, by forcing them to raise prices, which depresses unit sales, or sacrifice margins.
Apple sold 78.29 million iPhones in the fiscal first quarter ended Dec. 31, up from 74.78 million the year before. Analysts on average had expected 77.42 million, according to research firm FactSet StreetAccount.
That beat Samsung Electronics' 77.5 million smartphone sales in the quarter, according to tech data firm Strategy Analytics, the first time that has happened since the fourth quarter of 2011.
The results, which reflected the first full quarter of iPhone 7 sales, come at a time when global demand for smartphones is slowing and cheaper Android alternatives are flooding the market. Apple may also have benefited from Samsung's much-publicized recall of the its fire-prone Galaxy Note 7.
Apple is heavily dependent on the success of iPhones, which account for more than two-thirds of its total revenue.