We don't yet live in a cashless society, but digital methods of payments and the broader fintech industry have been on the rise, and that trend is likely to continue for a while. According to some estimates, the fintech industry will be worth $1.5 trillion by 2030, up from $245 billion in 2021.

While exact estimates over relatively long periods are tricky to pull off, analysts typically agree that this market will remain northbound, even if they disagree on the details. You can, therefore, profit from this opportunity if you put your hard-earned money into the right stocks. Let's consider two excellent candidates: PayPal (PYPL 1.41%) and Apple (AAPL 0.51%).

1. PayPal

PayPal is an easy and obvious choice for investors looking to ride the fintech coattails through the end of the decade and beyond. The company is one of the leaders in this industry and has built a highly recognizable brand name. It ended the first quarter with 433 million active accounts, an increase of 1% year over year.

PayPal's ecosystem becomes increasingly attractive to sellers as more buyers join in, and vice versa. Research from the data analytics company Nielsen shows that when retailers accept PayPal as a payment method, it leads to more repeat buyers and more purchases. So merchants have an obvious incentive to offer it as a payment option; consumers clearly trust the company. That's why PayPal's acceptance rate has been growing -- it jumped by 3% year over year to 79% among the 1,500 largest online retailers in North America and Europe, as of the end of 2022.

PayPal has encountered issues over the past year and a half, as inflation and other economic problems led to lower consumer spending. And while its business was extremely strong during the early days of the pandemic, things have cooled off since then, creating unfavorable comparisons. That's to say nothing of the foreign exchange dynamics that also harmed the company's revenue growth last year.

Still, PayPal has delivered decent financial results throughout. In the first quarter, revenue of $7.04 billion increased by 9% from a year ago, while total payment volume of $354.5 billion came in at 10% higher than the year-ago period. Adjusted earnings per share (EPS) of $1.17 were 33% higher than the comparable period of the previous fiscal year.

Payment volume, revenue, and earnings should continue growing as PayPal expands its acceptance rate and makes headway in other markets, including serving more brick-and-mortar retailers. That's why the company can deliver solid returns through 2030 and beyond.

2. Apple

Apple isn't a pure-play fintech company. The tech giant is best known for its iPhone and other sleek (and expensive) gadgets. But it has been making a conscious effort to ramp up its services segment, including its fintech offerings. They include Apple Pay; a buy-now-pay-later service; and a high-yield savings account.

Apple is not as recognized in the fintech industry as PayPal, but it's not a small player. As of the end of 2022, it had a 28% acceptance rate -- up 1% year over year -- with the same 1,500 online retailers among which PayPal's acceptance rate was 79%. By this metric it might seem like Apple isn't even competing in the same league as PayPal, but note that it was second among digital wallets in this category.

Besides, Apple's massive installed base should be instrumental in expanding its footprint in the industry. With more than 2 billion devices worldwide, the company doesn't even need to target consumers outside of its ecosystem to be successful. Merely targeting its loyal customers by introducing new fintech services, or seeking to ramp up existing services, could work wonders in the long run. That's why its fintech ambitions look attractive.

And, of course, investors get more than that by investing in Apple. Its services unit also offers Apple TV+, Apple Music, Apple Cloud, and more. The company remains a leader in smartphones and computer operating systems.

Its sales have dropped somewhat in the past couple of quarters, which isn't surprising considering the challenging economic conditions. In the second quarter of its fiscal year 2023 (which ended April 1), Apple's revenue of $94.8 billion dropped by 3% year over year, while its EPS remained flat at $1.52. But the services segment reported sales of $20.9 billion, 5.5% higher than the year-ago period and a record for the segment.

Apple's overall business should rebound once economic conditions get better. And over the long run, the company will benefit from its growing fintech business, and the rest of its high-margin services segment, to provide market-beating returns.