SAN FRANCISCO – Apple reshaped technology and society when Steve Jobs unveiled the iPhone seven years ago. Now the trend-setting company is losing ground to rivals that offer what Apple has stubbornly refused to make: smartphones with lower prices and larger screens than the iPhone.

The void in Apple’s lineup is a major reason why the company’s quarterly revenue may be about to fall for the first time in more than a decade, much to the dismay of investors who are worried that the company is losing its verve and vision.

Wall Street vented its frustration after Apple reported late Monday that it sold fewer iPhones than analysts anticipated during the holiday season. Apple compounded that disappointment with a forecast raising the possibility of a slight revenue decline in the current quarter. It would be the first time that Apple’s quarterly revenue has dropped from the previous year since 2003.

Apple’s stock shed $44, or 8 percent, to close Tuesday at $506.50, marking the company’s largest one-day drop in a year. The sell-off leaves the stock at about 28 percent below its peak of $705.07, reached in September 2012, when Apple’s leadership in smartphones and tablet computers was still generating robust revenue growth.

Since then, Apple has been relinquishing market share to Samsung Electronics and other companies that primarily make devices running Google’s Android operating system. Those competitors offer a broader selection of designs and prices than the iPhone and the iPad.

That trend is one of the reasons that Apple’s revenue growth hasn’t exceeded 6 percent in any of the last three quarters. Its quarterly revenue was consistently increasing by at least 20 percent two years ago and even exceeded 70 percent in the 2011 holiday quarter.

Apple remains in stellar shape financially. The Cupertino, Calif.-based company is sitting on nearly $159 billion in cash.

Smartphones in less-affluent parts of the world are selling for less than $200. By comparison, iPhones sold for an average of $637 in Apple’s most recent quarter. Even Apple’s cheaper iPhone 5C is just $100 less than the high-end 5S.

Meanwhile, a variety of Android phones boast screens measuring 5 to 6½ inches diagonally, while the latest iPhones are all 4 inches.

Apple’s share of the smartphone market fell from nearly 19 percent at the end of 2012 to about 15 percent last year, according to IDC. Jobs carefully cultivated Apple’s luxury image before he died in October 2011, and Cook has given no indication he will risk tainting it with an inexpensive smartphone sporting lower-quality parts.

“Our objective has always been to make the best, not the most,” Cook said Monday.

He said Apple will expand its horizons this year with new products to push it beyond smartphones and tablets. Analysts expect an Internet-connected smartwatch and maybe a television set that would run on the same software as the iPhone and iPad.

Apple also is preparing to sell an iPhone with a 5-inch display screen, according to unidentified people cited in a report this month in the Wall Street Journal.