SAN FRANCISCO — Since Apple said in January that it would bring back most of the $252 billion it held abroad under the new tax law, investors have wondered what the company would do with the enormous cash pile. On Tuesday, those investors learned that they are in line for a big chunk of the money.

Apple said it would buy back an additional $100 billion in stock, by far the largest increase in its already historic record of returning capital to investors. The company did not provide a timeline for the repurchases. Apple also increased its dividend by 16 percent to 73 cents a share, pushing past Exxon Mobil to become the largest dividend payer, according to S&P Dow Jones Indices.

Apple’s stock buyback fits into a broader trend of companies using the financial windfall from President Donald Trump’s tax cut to reward shareholders. Share buybacks, which are reaching record levels, are great for investors, including executives and employees, because they reliably lift stock prices by limiting the supply of shares for sale.

But critics say the actions can take money away from potential investments in hiring or research and development, and can increase economic inequality because they typically benefit wealthier people.

Investors should want companies to reinvest in themselves and their employees versus repurchasing their own stock to increase the share price, said William Lazonick, an economics professor at the University of Massachusetts, Lowell, who studies stock buybacks. “It’s nothing but a manipulation of the stock market.”

‘Very, very profitable business’

Luca Maestri, Apple’s chief financial officer, said in an interview that Apple was making significant investments in hiring, research and development, and manufacturing, “but we also have a very, very profitable business.”

He said that “because we’re making all the right investments all around the company, it makes perfect sense for us not to keep the cash on our balance sheet but return it to investors.”

No company has ever done stock buybacks like Apple. In the most recent quarter, Apple repurchased $23.5 billion in stock — the largest single stock buyback ever and more than the market value of 275 of the companies in the Standard & Poor’s 500-stock index, said Howard Silverblatt, a senior index analyst with S&P Dow Jones Indices.

Apple said Tuesday that it had now returned $275 billion to shareholders since 2012 and that it planned to finish its previous stock-buyback program in the current quarter, about nine months early.

In March, Sen. Tammy Baldwin, D-Wis., introduced legislation that would restrict companies’ ability to buy back stock, though the bill has little chance of passing.

‘Long-term value’

Other academics and investors cheered Apple’s continued returns to shareholders.

“People like to believe the stories that CEOs do things to boost the short-term stock price and line their own pockets,” said Alex Edmans, a finance professor at the London Business School. “But if you look at hundreds of examples, you find that stock buybacks do increase long-term value.”

He said that companies typically bought back stock only when they had extra cash that they would not reinvest otherwise, and that investors would spend that money elsewhere.

Apple said its profit increased 25 percent to $13.8 billion in the most recent quarter on the back of strong revenue growth for iPhones, the Apple Watch and its services business. Apple earned $2.73 a share, it said, beating Wall Street estimates by 6 cents. Revenue rose 16 percent to $61.1 billion.

The three months ending with March were Apple’s first full quarter selling its new flagship phone, the iPhone X. Analysts had pointed to signs, including the financial results of Apple’s suppliers, that the device and its sister iPhone 8 and 8 Plus had not revitalized Apple’s iPhone business as the company had hoped. Many analysts lowered their estimates for Apple in recent weeks as a result.

Apple said it sold 52.2 million iPhones in the quarter, or 3 percent more than a year earlier. But an 11 percent increase in their average price — driven by the $1,000 iPhone X — helped raise iPhone revenue by 14 percent.

Tim Cook, Apple’s chief executive, hit back at the notion that the iPhone business, which accounts for 62 percent of the company’s overall revenue, had little room to grow. “I don’t buy the view that the market is saturated,” he said.

Investors have also worried that Apple’s influence in China, the company’s No. 2 market, is waning amid stronger competition from Chinese rivals. But Apple’s results suggest that Chinese consumers are willing to pay for the pricier iPhones. Apple said revenue in mainland China, Taiwan and Hong Kong had risen 21 percent to $13 billion, the largest increase in 10 quarters.

And Apple’s services revenue, which includes iCloud and Apple Music subscriptions and its share of app sales, rose 31 percent to $9.2 billion. Apple said consumers had paid for more than 270 million subscriptions for its services or ones sold via its App Store, up from roughly 170 million a year earlier.