Warren Buffett is bullish on Apple, thanks to the behavior he's seen from consumers — even though he doesn't yet have the "courage" to try an iPhone X for himself.

The Berkshire Hathaway chairman and CEO told CNBC's "Squawk Box" on Monday that he was sent an iPhone X but he hasn't used it.

"A fellow sent me a '10' the other day, but I'm not using it yet," Buffett said. "Very nice fellow. He even explained it. I think he pretended he was writing to a 3-year-old child. He wrote me this very nice letter and explained what to do with it — how it wouldn't bite me or anything like that. I'm kind of screwing up my courage here and one of these days, I'll move."

When asked if he had an iPhone, Berkshire Hathaway Vice Chairman Charlie Munger said, "Of course not."

While neither uses the products, both men said they are optimistic about the company, thanks to Apple's management style and consumer reach. Apple's shares opened at a record high Monday, after Buffett said he wished he could own 100 percent of the company's stock.

"It has a position in consumers' minds, and a utility to them, that's very, very, very useful," Buffett said. "It's an incredible ecosystem that they've found ways to profit more from as they've gone along."