Apple reported earnings per share of $1.42 on revenue of $42.1 billion, easily beating analysts' expectations.
The company also gave sales guidance for the current quarter of $63.50 billion to $66.50 billion, at the high end of current analysts' estimates.
Wall Street expects the firm to hand in first-quarter earnings of $2.39 per share on $63.52 billion in revenue, according to a consensus estimate from Thomson Reuters.
Shares rose more than 1 percent in after-hours trading before easing.
Demand is "off the charts" for iPhone 6 and 6 Plus, said Tim Cook, Apple's CEO. He noted that the company is "excited by initial results for iPhone 6 in China."
"[W]e are heading into the holidays with Apple's strongest product lineup ever. We are also incredibly excited about Apple Watch and other great products and services in the pipeline for 2015," Cook said.
The company sold 39.3 million iPhones, generating about $23.68 billion in revenue, up 21 percent from a year ago. However, iPad sales declined 14 percent to $5.32 billion, with about 12.32 units sold.
Analysts polled by StreetAccount had forecast iPhone sales to rise to 37.41 million, while iPad shipments were expected to come in at 13.37 million.