After Apple Inc. (NASDAQ:AAPL) launched its new iPad Air 6 and iPad Pro models on Tuesday, Tesla and SpaceX CEO Elon Musk raised questions about the tech giant's huge research and development investment.

What Happened: Musk took to X, formerly Twitter, and responded to a meme comparing Apple's $30 billion R&D spend in 2023 to the marginal improvement in the thickness of its new 11-inch iPad Pro.

The meme was captioned "How It Started" vs "How It's Going." In response, the tech billionaire said that considering it was a lot of money that was invested in R&D, the Tim Cook-led company might be working on some "secret products."

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Why It Matters: This isn't the first time, Apple's substantial R&D investment caught Musk's attention. In January earlier this year, Tesla investor Sawyer Meritt highlighted that while the EV giant spent almost $4 billion in FY23, Apple and Microsoft invested $29.92 billion and $27.2 billion, respectively.

At the time, the Tesla CEO said, "There are gigantic differences in the effectiveness of R&D spending between companies."

Apple's newly unveiled iPad Pro features the M4 chip and OLED display. On the other hand, and iPad Air, now comes in two sizes, for the first time since its existence.

The new iPad Pro has a starting price of $999 for 11-inch and $1,299 for the 13-inch model. Similarly, iPad Air 6 starts at $599 and $799, for 11-inch and 13-inch models, respectively.

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