Apple's (NASDAQ:AAPL) stock has rallied more than 10,000% over the past two decades as iPods, iMacs, iPhones, iPads, and other new products breathed fresh life into the aging tech giant. That resurgence can be attributed to co-founder Steve Jobs, who returned as Apple's CEO in 1997 and disrupted the digital music, smartphone, and tablet markets with sleek, easy-to-use products.

Customers lined up to pay a premium for those products, and Apple locked them into its walled garden with its App Store and other software services. Jobs passed away in 2011, but Apple's stock has risen more than 500% since then as CEO Tim Cook upgraded Jobs' core products, introduced new devices like the Apple Watch, and expanded the company's software ecosystem with new services like Apple Pay, Apple Music, Apple Arcade, and Apple TV+.

Apple's iPhone SE.

Image source: Apple.

But under Cook, Apple has struggled with slowing sales of smartphones and tougher competition from Android devices. Jony Ive, who designed Apple's most significant hardware devices after Jobs' return, also left the company. Apple's increased focus on dividends and buybacks have also suggested its high-growth days were over.

Will Apple still generate more millionaire-making returns in the future? Or is it becoming a mature tech stock that is owned for dividends and stability instead of growth?

Apple's biggest weaknesses

Apple's biggest weakness is its overwhelming dependence on the iPhone, which generated 57% of its revenue last quarter. Apple's iPhone sales rose 2% annually during the quarter, but it's clearly running out of room to grow in the saturated smartphone market.

Apple's market share remains steady: It controlled 14% of the global smartphone market in the first quarter, according to Counterpoint Research, up from 12% a year earlier but down from 18% in the fourth quarter. However, IDC expects global smartphone shipments to decline at a compound annual growth rate of -0.7% between 2019 and 2024, which will make it increasingly difficult for Apple to grow its biggest business.

Apple is trying to boost its iPhone revenue with cheaper devices like the entry-level iPhone 11 and the new iPhone SE, but these new phones could merely help Apple to tread water instead of swim forward. On the bright side, the arrival of new 5G iPhones later this year could light a fresh fire under the business as 4G customers finally upgrade to 5G plans.

Apple's Mac and iPad businesses are also losing momentum, due to long upgrade cycles and intense competition. The COVID-19 crisis might temporarily boost demand for Macbooks and iPad Pros as more people work or attend classes remotely, but both product lines face intense long-term competition from cheaper Windows laptops, Chromebooks, and 2-in-1 devices like Microsoft's Surface.

In short, Apple's core hardware sales could stagnate over the next few years, and it could struggle to offset those declines with its new higher-growth businesses.

Apple's iPad Pro.

Image source: Apple.

Apple's greatest strengths

Apple's greatest strength is arguably its cash. It ended last quarter with $192.8 billion in cash, cash equivalents, and marketable securities, which gives it plenty of room for buybacks, dividend hikes, investments, and acquisitions.

Apple has already ramped up its investments in next-gen markets like augmented reality, virtual reality, artificial intelligence, and digital healthcare, and those seeds could eventually sprout and yield new hardware devices. It's also developing more first-party chips and components to streamline its supply chain and reduce its dependence on third-party suppliers.

Apple's AirPods and Apple Watch, two core components of the Wearables, Home, and Accessories segment that generated 11% of its revenue last quarter, are also faring well.

Apple reportedly sold over 60 million AirPods last year, according to Strategy Analytics, and accounted for 71% of all wireless headphone sales worldwide. The firm also estimates Apple Watch shipments rose 36% in 2019 to 30.7 million, as the entire Swiss watch industry's shipments fell 13% to 21.1 million. In April, Apple claimed over 75% of its Apple Watch buyers during the second quarter were new to the product.

Apple's family of subscription services hit 515 million paid subscribers last quarter, up from 125 million a year ago. It expects that figure to reach 600 million by the end of the year, which indicates its Services revenue, which rose 17% annually and accounted for 17% of its top line last quarter, will continue climbing as it locks more users into its walled garden.

The growth of that sticky ecosystem, which is tightly tethered to its hardware devices, could spell trouble for rivals like streaming video giant Netflix and streaming music leader Spotify. It also reinforces Apple's brand appeal and loyalty, which widens its moat against premium Android challengers like Samsung and Huawei.

So can Apple generate millionaire-making returns?

With a market cap of $1.4 trillion, it's highly doubtful Apple will replicate its massive gains of the past two decades. However, the stock isn't expensive at 22 times forward earnings, and it pays a passable forward dividend yield of 1%.

Investors who want millionaire-making returns should probably seek out higher-growth stocks with smaller market caps. However, investors who want stable stocks to hold for decades should stick with Apple -- which should be valued more like a consumer goods company than a tech one.