The number of quality stocks trading under $10 has never been a very high number. That's because good companies don't stay cheap for long -- their valuations grow rapidly as more investors hop on board and push the stock price to new heights.

With that in mind, here are three small-cap stocks currently trading for under $10 a share that probably won't stay that way for long and are ready for the big leagues. Each of these companies has a strong business model and the potential for long-term growth.

The first pick is Jumia (NYSE:JMIA), a troubled e-commerce company poised for a comeback. The second pick is Glu Mobile (NASDAQ:GLUU), a mobile game developer that can thrive amid the coronavirus pandemic. And the third pick is Sirius XM (NASDAQ:SIRI), a satellite radio operator that will benefit from its expansion into music and podcast management.

$10 bills are scattered on a surface

Image source: Getty Images.

1. Jumia: down but not out

Jumia has dramatically underperformed the market since its August IPO at $14.50 a share. The Africa-focused e-commerce company has struggled with fraud allegations on its platform and thin margins in some of its markets. However, Jumia's revenue is still growing at a respectable pace, and the company has a convincing plan to turn things around over the long term.

To boost margins, management has divested from less profitable markets such as Rwanda, Cameroon, and Tanzania to focus on larger markets like Egypt, Nigeria, and South Africa, where consumers have larger purchasing powers and better access to the internet.

Internet access is a big driver of online retail adoption, and Jumia is well-positioned to benefit from several promising projects aimed at getting more Africans online.

American tech giant Facebook has partnered with several top telecom companies to build a 23,000-mile subsea internet cable called 2Africa to link 16 African countries to Europe and the Middle East. The connection is expected to go live by 2023 or 2024 and dramatically reduce bandwidth costs and improve internet speeds and access on the continent -- three massive enablers for Jumia's revenue growth.

Jumia reported first-quarter earnings on May 13, and the results show resilience amid the COVID-19 pandemic. Annual active customers grew by 51% to 6.4 million, while marketplace revenue grew 22% to 19.1 million euros ($21.48 million).

2. Glu Mobile: Coronavirus-proof growth

Glu Mobile is a leading mobile game developer that operates an attractive "freemium" model. Games are free to download, but players have to shell out money for expanded functionality and more fun.

While some in the gaming community may find this business model manipulative (especially with so-called pay-to-win games), it can be a cash cow for investors because it encourages larger numbers of players to download the game without being scared away by upfront costs.

Glu Mobile is performing well during the coronavirus pandemic, with shares up by around 61% year to date compared to a 1.5% decline in the S&P 500 over the same period. That's because the company stands to benefit from increased stay-at-home demand for entertainment due to social distancing and government-mandated lockdowns.

The company reported first-quarter earnings on May 8, and the results show respectable growth in these uncertain times. Revenue increased 12% to $107.3 million, while bookings were up by 15% to $106.5 million. Glu's strong top-line performance was powered by growth in Design Home and the Tap Sports franchise, which grew bookings by 10.8% and 21.3%, respectively. The company can drive future growth by adding to its portfolio of intellectual properties. Glu launched Tap Sports Baseball and Disney Sorcerers Arena in the first quarter, with plans to launch Tap Sports Fishing and several other games in 2021.

3. Sirius XM: Synergistic acquisitions

Like Jumia, Sirius XM has seen better days. The stock peaked at $66.50 per share during the tech bubble in 2000, before falling to $5.80 at the time of writing. However, despite its troubled history, Sirius boasts a respectable near-term recovery, with its share price up by around 511% since 2010, compared to a 205% rise in the S&P 500 over the same period.

Sirius's acquisition-driven strategy can help power its next leg of long-term growth and help the stock continue beating the market.

On June 17, Sirius announced the acquisition of Simplecast, a podcast management platform that helps creators manage their content. Management hopes to synergize this new asset with Sirius's monetization platform, AdsWizz, to help podcasters publish content and generate revenue in the same place. This is a great opportunity for Sirius, because podcasting is a super growth industry projected to expand at a compound annual growth rate of almost 30% through 2022 as it becomes more mainstream.

A push into podcasting will also help Sirius diversify its business model outside of satellite radio and music.

Meanwhile, Sirius's core radio business is performing well, despite coronavirus-related challenges in the economy. The company reported first-quarter earnings on April 28. Total revenue increased by 12% and totaled $1.95 billion, powered by strong performance in the advertising business, which saw sales soar by 36% to $285 million year over year.