For years now, Warren Buffett has iconically sported a $20 Samsung SCH-U320 flip phone, but times, they are a-changin'. The Berkshire Hathaway (NYSE: BRK.B) CEO, who is often considered to be the greatest investor of all time, has finally given in and upgraded to an iPhone 11. 

On the same day of this momentous occasion, Buffett sat down with CNBC, and when asked about iPhone maker, Apple (NASDAQ: AAPL), he responded: "It's probably the best business I know in the world... I don't think of Apple as a stock. I think of it as our third business." 

High praise indeed from the world's third-richest individual. 

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What is Buffett's stake in Apple? 

As mentioned above, Apple is Berkshire's largest single holding ahead of the likes of American Express (NYSE: AXP), Coca-Cola (NASDAQ: KO), Bank of America (NYSE: BAC), and Wells Fargo (NYSE: WFC). Berkshire Hathaway is also Apple's second-largest investor, owning 245 million shares, or 5.7% of the tech giant.

Traditionally, Buffett was not a fan of tech stocks and only began to take notice of Apple when one of his portfolio managers bought $1 billion in Apple stock back in 2016. Its stake is now valued at roughly $72 billion. The investment has paid off for Buffett with Apple stock up nearly 140% in the past 5 years, and 85% in 2019 alone, compared with the S&P 500's (NYSEARCA: VOO) 28% gains.

Buffett appears to be thankful for these returns as well, stating in the CNBC interview: "I should have appreciated it earlier."

A bad day for the market 

Not even praise from Warren Buffett himself could prevent Apple's stock price from falling nearly 5% on Monday. Just last week the company saw its stock price dip after it updated guidance on iPhone revenue for the quarter as the coronavirus slowed production in China. However, Apple investors were not too put off by this, proving that the iPhone no longer dictates Apple's stock price. 

Apple's decline on Monday, however, was part of a wider market fall in reaction to increasing coronavirus fears. 

The Dow Jones Industrial Average actually fell more than 1,000 points, or 3.5%. European equities crumbled, led by Italy's 6% slump as coronavirus cases in the country rose, while the world's second-largest economy, China, has all but shut down.

Airline and travel stocks suffered heavy losses, with the likes Delta (NYSE: DAL) and Booking Holdings (NASDAQ: BKNG) falling more than 6% and 7% respectively. 

A bad time for risky investments

There is never a good time for a market fall-off, but it seems especially unfortunate for riskier stocks which have made massive gains in recent weeks, such as the hugely popular electric car maker Tesla (NASDAQ: TSLA). Two stocks who are enjoying the limelight right now -- much like Tesla -- are Beyond Meat (NASDAQ: BYND) and Virgin Galactic (NYSE: SPCE), who will also announce earnings this week.

Plant-based meat producer Beyond Meat saw its stock jump 46% in January alone and continue to steadily climb in February, while Virgin is fresh off of an eight-day streak of record gains, with the company up close to 200% in 2020 so far. 

Virgin will announce its second-ever earnings report after market close today, with analysts expecting a loss of $0.20 per share on revenue of $1.1 million. Beyond Meat is reporting on Thursday, and is expected to announce earnings per share of $0.42 on sales of $495 million.

MyWallSt operates a full disclosure policy. MyWallSt staff currently hold long positions in companies mentioned above. Read our full disclosure policy here.