Many new and exciting companies have come to the public markets over the past two years, often by merging with special purpose acquisition companies, or SPACs. Investors have favored large-cap value stocks for much of the past six months, leaving a handful of these up-and-coming tech stocks at discounted prices.

These three former SPAC stocks, in particular, stand out due to their innovative business models and large growth opportunities that long-term investors could find rewarding. It doesn't take a huge investment to get started; each of the tech stocks below costs less than $20 per share.

1. A new way to monetize mobile games

Skillz (SKLZ -0.75%) is a technology platform that enables mobile games to support fair competition for real cash prizes. Mobile game developers have traditionally relied on in-game purchases or ads to generate money from their games, but this diminishes the gaming experience because they make the games unfair ("pay-to-win") or intrusive.

Person in suit throwing money into the air.

Image Source: Getty Images.

On Skillz, gamers pay into a "pot," and the winner of each gets that money minus a portion that Skillz keeps. The company has successfully enticed gamers to compete, converting 19% of the company's 2.4 million monthly active users into paying players as of the second quarter of 2021.

The company estimates that the mobile gaming market is worth $86 billion and has grown 23% per year since 2015. Skillz is just getting started, guiding to $376 million in revenue in 2021, a 63% year-over-year increase. Over the next 18 months, Skillz will be launching NFL-themed games on its platform and entering a new market in India.

2. Redefining how we buy and sell homes

Opendoor Technologies (OPEN -4.67%) is an "i-buying" company that lets homeowners buy and sell their homes online via Opendoor's digital platform. Opendoor provides sellers with cash offers and navigates the closing process through its website and/or smartphone app. This cuts the real estate agent and their traditional 6% commission out of the transaction (Opendoor charges a 5% fee), and more importantly, makes selling a home a much more straightforward process.

The company acquired 8,494 homes in Q2 2021, just a tiny fraction of the 6 million to 7 million homes sold each year in the United States. The real estate market is wide open to Opendoor, and the company is working to grow as fast as possible.

CEO and founder Eric Wu said during the company's Q2 earnings call that the business is on a run rate over the second half of this year to surpass the company's revenue projections for 2023, pulling expected revenue growth forward two years ahead of schedule.

3. Creating a new industry with spacial data

Matterport (MTTR) is a 3D technology company that converts real-life buildings and spaces into digital replicas. Users can use special cameras or smartphones to photograph spaces, and Matterport will rebuild them digitally. This technology is being used in several ways, including home tours, virtual storefronts, and more.

The company generates revenue by selling camera hardware and subscriptions for customers to manage their virtual spaces. Matterport currently has 5.6 million virtual spaces under management and has practically pioneered this market. It claims that it has 100 times more virtual spaces than all of its competitors combined.

Matterport's business is on a $118 million revenue run rate as of its 2021 Q2, making the business very young. It is poised for significant long-term growth as the de-facto leader in digitizing spaces because there are so many more spaces and properties yet to become digital. Management estimates that at 200 million spaces (remember, it currently manages just 5.6 million), the business would generate $12 billion in annual revenue, and that would still represent just 1% market penetration. It's possible that competition could enter the picture, but Matterport is currently enjoying a clear first-mover advantage.

Here's the bottom line

All three of these companies have some things in common. They are attempting to disrupt large industries with new and innovative business models. This makes them a little riskier, but they have shown encouraging growth and execution thus far.

With each at less than $20 per share, investors have more opportunities than ever to participate in these potentially emerging companies. If things go well, these stocks may not stay under $20 per share for very long.