E-commerce stocks have exploded, especially tech companies that connect retailers with customers online. Investors in Shopify, MercadoLibre, and The Trade Desk have doubled their money so far in 2020, and the year's not over yet! If you haven't bought in yet, though, those shares are looking pretty pricey right now.

No worries -- there are plenty of other big trends in the market, and lots of companies poised to ride them to big growth over the next ten years. Here are three stocks that are much smaller than Shopify, but look ready to ride that same explosive growth trend in the future.

A man traces an upward curve with his finger.

Image source: Getty Images.

Livongo Health: Harnessing technology for better health

Livongo Health (LVGO) has also seen explosive growth in 2020, with shares up more than 400% year to date. However, even though sales of the company's diabetes-monitoring platform have grown, it's still addressing barely a sliver of its potential market.

While many diabetics rely on frequent at-home testing to monitor blood glucose levels, Livongo's platform goes a step further, using data analytics to actively assist them in managing their condition. That's expected to result in better health outcomes over the long term, which should reduce overall healthcare costs. Livongo has also adapted its technology to offer a platform for managing hypertension.

Like most healthcare options, Livongo's subscription platform is only available to customers whose employers -- and their healthcare plans -- have signed up to offer it. That list is small, but constantly growing. For example, Livongo announced that four new Fortune 500 companies have signed up this year, and other existing customers have expanded their support. However, with an estimated 10.5% of the U.S. population living with diabetes, and almost half of U.S. adults living with hypertension, Livongo has tons of room to grow.

Upwork: Expanding the gig economy

When most people think of the "gig economy," they think of drivers for Uber or Lyft. However, freelance work comes in all shapes and sizes, and frequently involves a specialty niche, like accounting, law, or technical writing.

Companies looking for a contract worker with a specific skill set for a short-term project may not know how much to offer or what questions to ask to make sure an applicant is qualified. Online freelancer marketplace Upwork (UPWK 0.44%) takes out the guesswork by allowing companies to post project descriptions on its site, and receive confidential bids from contractors interested in the work. Companies can interview, hire, and even pay the freelancers through Upwork's site. 

Workers who are between jobs or underemployed have long turned to freelance work to provide additional income, and gig economy workers with niche skills can struggle to find clients. As the disruption of the traditional workplace continues, Upwork is poised to take advantage. 

Stag Industrial: An alternative bet on e-commerce

Yes, e-commerce has already exploded, but that growth is only likely to continue over the next decade as more and more people discover the ease of shopping online. And while tech companies that support e-commerce have seen their shares double in 2020, Stag Industrial (STAG 0.48%), a real estate investment trust (REIT), has notched growth of just 7.8%.

Stag buys industrial facilities and leases the space to clients. Its strategy has been to avoid pricey real estate in major markets like New York City, instead looking for spaces that are in smaller towns that can still serve population centers. For example, you've probably never heard of Burlington, New Jersey or Taunton, Massachusetts, where Stag owns distribution centers. But you've heard of Philadelphia (just 20 miles from Burlington) and Boston (40 miles from Taunton). Stag signed major leases in both towns this year to an unidentified "dominant e-commerce tenant" (which may have been Amazon). 

As more companies move to e-commerce, demand for warehouse and distribution space should only grow. Stag is in the right niche at the right time, and its current 4.4% dividend will reward investors for waiting. 

Growth: A risky business

Of course, these trends may not pan out. Smaller companies have more room to grow, but there's always the possibility that another small competitor might put out something better, or that the company will be outgunned by a major established player that enters the space. And then some trends just never catch on. 

While growth investing is inherently risky, the trends of improving healthcare technology, a growing gig economy, and e-commerce growth should be huge. And that makes Livongo Health, Upwork, and Stag Industrial good bets for huge growth.