Apple has sold more than 271 million of the devices since then, and in the company's last fiscal year ending in September, the iPhone generated $80 billion in sales to account for more than half of the company's total revenue.
But Apple's upgrades of the iPhone in the past two years have disappointed gadget lovers who have been clamoring for Apple to do more to stay in front of device makers relying on the free Android software made by Google Inc. For instance, there were high hopes for a larger iPhone screen with the release of the 2011 model, but Apple waited until last September to take that leap. And when Apple moved to a larger display screen with the iPhone 5, it didn't include a special chip to enable users to make mobile payments by tapping the handset on another device at the checkout stand. Such a mobile payment feature is available on some Android phones.
Finally, Apple has insisted that wireless carriers subsidize so much of the iPhone's cost in exchange for customers' two-year commitments on data plans that the carriers make little or no money by selling the devices. That has prompted more wireless carriers to tout less expensive Android phones in their stores, undercutting the demand for iPhones, said Darren Hayes, who has been studying the shifting market conditions as chairman of the computing systems program at Pace University in New York.
Through the third quarter of last year, Android devices represented 75 percent of smartphone shipments worldwide according to the research firm International Data Corp. That was up from 58 percent at the same point 2011. Meanwhile, Apple's share of worldwide smartphone shipments has fallen from a peak of 23 percent in the fourth quarter of 2011 to 15 percent in the third quarter of last year.
Samsung Electronics, in particular, has been benefiting from the growing popularity of its Android-powered phones, led by its Galaxy S line. The company said Monday that it sold more than 100 million Galaxy S phones in less than three years. It took the iPhone nearly four years to reach that milestone.