Artificial intelligence (AI) has created some big winners, but a lot of the money has already been made in big names like Nvidia and Microsoft. For investors willing to take on more risk, there are smaller players using AI in unique ways whose stocks could still have massive upside if they deliver.

Two such growth stocks are SoundHound AI (SOUN -0.70%) and AppLovin (APP 4.13%). These are speculative bets, but they each have the kind of disruptive technology and accelerating growth that could turn a small investment into something far bigger over time.

Let's take a close look at why these two stocks have millionaire-making potential.

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Image source: Getty Images.

SoundHound AI

SoundHound is betting that the future of AI will be conversational and voice-driven. The company has always been strong in voice AI, building a solid presence in the automotive and restaurant markets. More recently, it expanded its scope with the acquisition of Amelia, a leader in conversational intelligence software. That deal gave SoundHound exposure to industries like healthcare and financial services while also becoming the foundation for its next-generation AI platform.

With the launch of Amelia 7.0, SoundHound has entered the agentic AI market. Unlike traditional voice assistants, these AI agents can act independently and complete tasks on their own. As with other agentic AI platforms, building these agents requires little or no coding, but it is SoundHound's voice-first technology that helps differentiate it. SoundHound also recently added real-time visual recognition, expanding its capabilities beyond voice. That combination of voice and vision AI could open the door to lots of new applications.

The early results have been eye-catching. In its most recent quarter, revenue soared 217% year over year to $42.7 million, easily topping expectations. Management raised its full-year outlook and said it is on track to hit adjusted EBITDA profitability by the end of 2025. The company is already migrating 15 of its largest enterprise customers to the new Amelia platform.

This is still a small-cap stock with plenty to prove, but SoundHound has shown it can adapt quickly in a fast-changing AI landscape. Meanwhile, having an AI voice engine that better understands what you are saying has the potential to be a huge advantage. If you've ever used the voice feature on an AI chatbot that doesn't understand you, you know how frustrating that can be, and SoundHound has the potential to be the company that solves this issue. If it succeeds in building a leadership position in multimodal agentic AI, the upside could be enormous.

AppLovin

AppLovin has quickly become one of the most explosive AI growth stories on the market. The company shed its legacy gaming business and is now a pure-play adtech platform powered by its AI engine, Axon 2.0. The technology optimizes ad targeting, bidding, and placement, and it has become the go-to platform for mobile game developers.

The numbers tell the story. Revenue jumped 77% in its most recent quarter to $1.26 billion, while adjusted EBITDA nearly doubled to $1 billion. Earnings per share (EPS) surged from $0.89 to $2.39. What makes this even more impressive is that AppLovin has grown at this breakneck pace while simultaneously lowering its expenses and expanding gross margins. That kind of operating leverage shows the strength of its business.

The gaming market alone is a massive opportunity, with management expecting 20% to 30% annual growth going forward. But AppLovin is only getting started. It is piloting its AI ad platform with e-commerce and web-based advertising, while also preparing to launch a self-service ads manager. That should significantly expand its customer base by putting more control in advertisers' hands. The company also plans to open its platform internationally, tapping into a user base where the majority of gamers already reside outside the U.S.

Short-sellers have tried to poke holes in the story, but thus far, AppLovin has answered every challenge by continuing to deliver outsized growth in revenue, profits, and free cash flow. If Axon 2.0 proves to be as effective outside of gaming apps as it has inside them, the stock could have another huge boost higher.