Since going public in mid-2015, e-commerce platform developer Shopify (SHOP 0.41%) has nearly quintupled in value, for around a 60% annual compounded growth rate. Of course, predicting those kinds of returns is impossible, but Shopify's business model represents a unique opportunity that hit the market at just the right time.
Yet Shopify isn't the only business with compelling arguments in its favor. We asked three of our Motley Fool investors for growth stocks that they like that have the potential to post returns that would put Shopify's own to shame. They chose gaming specialist Activision Blizzard (ATVI), electric car maker Tesla (TSLA 1.93%), and streaming device maker Roku (ROKU 1.88%).

Image source: Getty Images.
The king of video games
Travis Hoium (Activision Blizzard): Activision Blizzard is well known for being a PC and console game company with games like Call of Duty and World of Warcraft. But I think the company is set up for long-term success because of its willingness to adapt to digital sales and early exploitation of esports. The company generated $7.02 billion in revenue last year and $2.21 per share in non-GAAP earnings in large part because of $5.43 billion of bookings from digital channels and we're only now beginning to see the potential of esports.
Data source: ATVI Revenue (TTM) data by YCharts.
What I want to highlight here is the power of esports in growing beyond the current gaming model. The Overwatch League is a model esports league with team owners like Robert Kraft (New England Patriots) and Stan Kroenke (Los Angeles Rams) and multi-million dollar advertising deals. If esports continues to grow and attract more viewers than NFL games, this could be a booming business long-term. Twitch TV has already agreed to a reported $90 million two-year deal to show Overwatch League on its streaming platform and advertising deals with HP and Intel are both reportedly worth $10 million-plus over a two-year period. The beauty of esports is that Overwatch League may be just the beginning. Activision Blizzard can replicate the success of one league with new games, effectively creating multiple sports leagues that it owns.
Between the organic growth in existing console, PC, and mobile platforms and the growth potential in esports, Activision Blizzard has a bright future for long-term investors.

Image source: Tesla.
Vroom, vroom! Like Shopify, Tesla could zoom
Rich Smith (Tesla): Shopify stock is up more than four times in value over less than three years since coming public. And yet, over the course of those three years, the company's losses have doubled (from $19 million in 2015 to $40 million last year), and its rate of cash burn, -- less than $1 million in 2015 -- has swelled to more than $12 million burnt over the past 12 months.
So why is Shopify stock so popular? Sales growth appears to be investors' primary motivator. In 2015, Shopify took in $205 million in revenue -- up more than eight times from the $24 million in sales booked in 2012. Last year, Shopify's sales had swelled to more than $673 million, another three-fold increase -- close to a 100% annualized growth rate.
Is there any other company we know about that can match that kind of performance? Actually, there is: Tesla.
Like Shopify, Elon Musk's electric car company, Tesla, has posted astounding sales growth off of a very small base. It may be hard to recall today, but as recently as 2011, Tesla had only sold 1,500 or so cars since its creation. Even today, with more than 250,000 cars sold, Tesla's entire "lifetime achievement" is fewer cars than GM sells in a month. Growing off its exceedingly small base, finviz.com calculates that Tesla's sales have grown at a very Shopify-like growth rate of 95%, annualized.
Granted, Tesla still isn't profitable. Then again, neither is Shopify, and that doesn't seem to be slowing down its stock growth. And like Shopify, Tesla is expected to turn profitable as early as 2020. If you're looking for a rocket stock that could put Shopify's returns to shame, look no further than Tesla.

Image source: Best Buy.
Tune in to this unlikely winner
Rich Duprey (Roku): Shares of streaming device maker Roku had been surging recently as it put together a string of positive press releases, not least of which was the announcement its Roku Channel would soon be appearing on Samsung smart TVs.
That all seemed to get dashed when Amazon.com and Best Buy announced an expanded partnership that would see the e-commerce giant's new Fire TV Edition smart TVs appear exclusively in the electronics retailer's stores. And with Best Buy becoming a third-party merchant on the Amazon site, it would be a closed loop where such TV sales would all go through the bricks-and-mortar retailer.
Shares of Roku tumbled on the news, despite the fact that Roku's own enabled TVs would still be sold at Best Buy. The market assumed that with Amazon entering the TV space with the last remaining electronics superstore, Roku would be squeezed out. But by being exclusive to Best Buy, it gives Roku unfettered competition in all other retail outlets.
That's not necessarily the case and it looks like an overreaction that depressed the already beaten down media company. That gives investors an opportunity to profit on what is otherwise a growth stock that should be able to emulate Shopify's returns in the future.
Roku has said its game plan is not to be selling devices, but rather to grow the number of users and build up the amount of content they stream.
At the end of the fourth quarter, Roku had 19.3 million active user accounts who streamed 4.3 billion hours of content in the quarter, a better than 15% increase from the end of the third quarter and 44% jump from a year ago. Hours of video streamed has risen 55% over the past year. Now that it is expanding beyond its own controlled ecosystem with the Samsung deal, other partners may also sign on and those figures could increase exponentially.
Roku's stock may be down for the moment, but with no guarantees that Amazon will actually succeed and the significant installed base the streaming device maker already has, it may not be long before Roku's stock starts heading higher.