Apple Inc. operations chief Jeff Williams rekindled speculation on Wednesday, May 27, that the California tech giant might spend some of its massive cash hoard on automotive ventures. Though he stopped short of addressing his company’s rumored work in developing an electric vehicle, the comments reignited speculation that Apple is taking its future in the automotive world seriously.

The car is the ultimate mobile device, isn’t it?” Williams told an audience at the Re/code conference in Rancho Palo Verdes, California, a gathering of tech and media leaders.

Williams was answering a question from the audience about what the company could do with its $193.54 billion in cash besides the stock buybacks and dividends that some shareholders are demanding, including noted investor activist Carl Icahn.

When pressed on the car topic, Williams steered the conversation toward Apple CarPlay, which integrates the iPhone into a vehicle’s dashboard computer. Automakers are starting to release vehicles that are compatible with both CarPlay and Google’s Android Auto, and clearly this has been high on Apple’s automotive agenda in recent years.

In March, Apple CEO Tim Cook dodged questions about whether Apple would acquire Tesla Motors, the Silicon Valley maker of the Model S luxury electric car. In one way, the move makes sense because Tesla’s engineers headed by futurist CEO Elon Musk have done much of what a tech company would need to do to start making cars. And Tesla is burning through cash so quickly it will need more capital soon. Telsa had $1.51 billion in cash at the end of March, down from $1.91 billion at the end of 2014. A few billion dollars from Apple’s cash hoard would go a long way.

“That Tesla still requires more capital shows you that automotive is a very resource-intensive business,” said Thilo Koslowski, vice president and automotive practice leader at technology research firm Gartner Inc. “But I don’t think Apple wants to be a bank. Any partnership with Tesla would have to go well beyond that.”

Indeed, the relationship would be complicated.

Musk isn’t likely to cede control of Tesla, so any investment in his company would have to secure his position. And that could be a deal breaker for a company like Apple, which prefers to be in complete control of what it produces.

Apple has never said publicly that it wants to make cars, but it also hasn’t denied reports, citing anonymous insiders, that it’s working at a secretive facility in Cupertino to produce an electric car by 2020.  

Automakers are starting to release vehicles that are compatible with both CarPlay and Google’s Android Auto. At the same event on Wednesday, General Motors CEO Mary Barra announced that CarPlay and Android Auto will appear in 14 Chevrolet cars in 2016, including the $13,000 Chevy Spark mini.

Tesla Motors Inc. (NASDAQ:TSLA) shares dropped 0.06 percent to $247.43 in after-the-bell trading on Wednesday. The shares are up more than 11 percent since the start of the year.

Apple Inc. (NASDAQ:AAPL) shares dropped 0.11 percent in after-hours trading, to $132.08. Apple’s stock is up nearly 20 percent since the start of the year.