Despite no official confirmation of its existence, plenty of buzz remains around the rumored Apple electric car.
Interest in what is known as "Project Titan" largely rests on Apple's reputation for innovation, despite far too little information for analysts to make even educated guesses about specific features or design elements.
Nonetheless, Tesla Motors CEO Elon Musk believes Apple is building an electric car—and that the tech company could eventually provide competition for Tesla.
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At a conference last week, Musk said Apple will start volume production of electric cars by 2020, according to the San Francisco Business Times (subscription required).
Apple will "probably make a good car and be successful," Musk said.
He said it is "great that they're doing this," but also questioned whether Apple will get cars into production fast enough to make an impact on the market.
After mentioning the 2020 estimate, Musk asked "Is that too late?"
While Apple may challenge Tesla with electric cars of its own, Musk said Google probably won't enter the car business as a direct competitor.
Google has "done a great job at showing the potential of autonomous transport," Musk said, "but they're not a car company."
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Instead, Google may license its technology to other companies, Musk believes.
Recently, Google did in fact announce a partnership with Fiat Chrysler Automobiles (FCA) for autonomous-car development.
The two companies will test a fleet of autonomous Chrysler Pacifica Hybrid plug-in hybrid minivans, but commercial applications have not been discussed.
Google autonomous car prototype
Musk has been convinced that Apple is aiming to build its own car for some time.
In January, he said the Apple car project was an "open secret," pointing to the number of engineers with automotive experience hired by the company recently.
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Some of those engineers came from Tesla, leading to some bad blood between the two companies.
Musk previously referred to Apple as the "Tesla Graveyard," implying that only people who couldn't hack it at Tesla would leave to work there.