Shares of Apple (NASDAQ:AAPL) have risen sharply recently. The stock is up 25% in the past three months and 38% since Jan. 3 -- the day after Apple CEO Tim Cook warned that fiscal first-quarter revenue would be significantly worse than management's initial guidance for the period. Is it too late for investors to buy shares?

In December, when shares were trading around $165, I argued that the stock was a buy due to the company's momentum in services and its opportunity to further monetize users across its large installed base of active devices. With shares up 18% since that article, is the stock still attractive?

Apple store in Bangkok, Thailand.

Image source: Apple.

A conservative valuation

Shares of Apple closed the trading day on Thursday at about $195. While the stock certainly isn't as attractive as it was, it's still a compelling stock at this level.

Its price-to-earnings ratio, for instance, is just 16.1 at the time of this writing. This compares to an average price-to-earnings ratio of 21 for stocks in the S&P 500. In addition, considering Apple's trailing-12-month earnings per share is up 17% year over year and that the company even managed to achieve record EPS in its worse-than-expected first quarter, a P/E of 16.1 for Apple seems low.

Also, Apple's trading at an attractive valuation relative to its underlying free cash flow, or the cold, hard cash left over after both operations and capital expenditures are accounted for. Apple generated a whopping $62 billion in free cash flow over the trailing 12 months, giving the Cupertino, California-based company massive cash flow for things like dividends, share repurchases, and acquisitions. And don't forget Apple's net cash of $130 billion. Apple, therefore, trades at just 15 times its free cash flow and seven times its net cash.

Sure, Apple could face earnings and free cash flow headwinds during fiscal 2019, as the company is up against tough comparisons in fiscal 2018. In fact, the consensus analyst estimate for Apple's fiscal 2019 earnings per share is $11.40, down from $11.91 in fiscal 2018. But analysts also expect a prompt return to growth, guiding for earnings per share of $12.76 in fiscal 2020.

Check out the latest earnings call transcript for Apple.

Key catalysts

Rounding out the reasons why Apple stock is attractive today is the company's prospects beyond iPhone.

Apple's second-largest segment, services, is growing rapidly and there's no slowdown in sight. Services revenue has increased from less than $8 billion in calendar 2010 to more than $41 billion in calendar 2018. And growth in the segment remains strong, with trailing-12-month services revenue up 27% year over year.

In addition, Apple's "other products" business, which was recently renamed to "wearables, home, and accessories," saw trailing-12-month revenue rise 34% year over year.

Highlighting how important these two catalysts are becoming to Apple's growth story, they account for 22% of the tech giant's total revenue when combined.

Apple's conservative valuation and its strong prospects for its fast-growing services and wearables, home, and accessories segments mean shares still look attractive around $200.