Shares of Apple got a boost as Warren Buffett's Berkshire Hathaway announced a new $1 billion stake in the tech giant and CEO Tim Cook toured China. The stock was the best performer on the Dow Monday, up more than 3.7 percent .
Apple's stock closed at $93.88 a share, down from its 52-week high of $132.97. The shares have fallen nearly 11 percent year to date, after the company missed analyst expectations for quarterly earnings and revenue, and iPhone sales sank for the first time ever.
Buffett's company is buying in. Portfolio managers at Berkshire bought a $1 billion stake in Apple, according to a Securities and Exchange Commission filing Monday. The company's new position in Apple totals 9.8 million shares.
Berkshire's vote of confidence should be a good omen for investors worried about China, and searching for Apple's long-term story, according to Gene Munster, managing director and senior research analyst at Piper Jaffray.
"Warren Buffett kind of lays some of those anxieties a little bit to rest," Munster told "Squawk on the Street" on Monday. "He believes it's going to be around for a long time and going to be a worthwhile investment, I think that's the real takeaway."
"You worry a little bit — and maybe more than a little — about China's attitude," Icahn told CNBC's "Power Lunch" after selling shares in late April, later adding that China's government could "come in and make it very difficult for Apple to sell there."
David Einhorn's Greenlight Capital initially joined Tepper in Icahn in scaling back shares of Apple. But according to a regulatory filing submitted Monday, Greenlight raised its stakes to 8.21 million shares from 6.28 million in the previous quarter.
Sales in China, once the tech giant's fastest growing market, fell to $12.49 billion in the second quarter, a 26 percent decline year over year, the company said.
Apple's Cook was in Beijing on Monday, meeting with Chinese officials and internet firms. The tech giant announced a $1 billion investment in ride-hailing company Didi Chuxing last week, a move which Munster said could also ease skittish investors.
"What this does, is show that Tim Cook is on the offense in China," Munster said, adding that the Didi Chuxing investment signals a shift from core hardware to services.
Munster has a $153 price target and an "outperform" rating on the stock. Despite the shares' recent dip, he said the markets are wrong when it comes to Apple.
"We're in the camp that the market needs to catch up and the biggest reason is that growth is going to return," Munster said. "That's the message with having Warren Buffett involved."