CARY - From hungry zombies to air traffic control training, Spark Plug Games navigates the unpredictable gaming industry by diversifying its products and always looking for new opportunities.

“It’s always been the nature of the game industry,” said John O’Neill, 41, owner of the Cary-based company. “You never stop learning. It is a constant consumption of new technology, new trends and new directions.”

Today’s gamers include millions of individuals from diverse backgrounds, according to the Entertainment Software Association. The average player is 30 years old and has been gaming for 12 years. About 47 percent of all gamers are women, and consumers spent $24.75 billion on video games, hardware and accessories in 2011, according to the association

Spark Plug Games, an independent software and game development company, has created about 60 products, and O’Neill has developed a business model that seeks to program fun into short, high-quality games and educational applications.

Those products, built for handheld devices, personal computers and game consoles, include games developed for other companies to sell as their own; games that have been modified to fit a marketing or trade show need; and applications that seek to improve a skill or promote an industry.

After graduating from N.C. State University with a computer science degree in 1996, O’Neill rotated in and out of the gaming industry before founding Spark Plug Games with Ben Lichius in 2008. Lischius was based in Cary until he moved Pittsburgh two ago. The pair planned to develop high-quality games with smaller scopes that would appeal to mass markets, and wanted to deliver the games through a digital format to console companies such as Nintendo and Microsoft.

Ultimately, O’Neill said, they wanted to escape the chaotic schedules associated with trying to build larger, intricate products under unrealistic and rigorous deadlines.

Early on, a publisher approached Spark Plug with a deal to build a game for Dairy Queen. O’Neill took the job and built Spark Plug’s first “casual game,” a simple product that seeks to appeal to a mass audience.

“That kind of opened the opportunity for the casual games and the casual-game market,” he said.

Initially, Spark Plug sold casual games and related licensing rights to companies, such as Big Fish, an online outlet for games.

However, O’Neill said it was hard to let go of the products that they had worked for months to develop, and the compensation barely covered development costs.

“When you put so much effort into coming up with great game ideas, it was really tough giving that away,” O’Neill said.

Over the past two years, an increase in mobile devices and more access to digital games has created additional avenues for Spark Plug to monetize their products by selling the opportunity for advertising to be integrated into free games.

“Plight of the Zombie” is one of Spark Plug’s more successful games, O’Neill said.

O’Neill used networking opportunities and contacts to connect with companies, schools and government agencies in need of “serious games,” or apps that provide training, simulations or education, including an iPod Touch app that the U.S. Federal Aviation Administration uses to help teach air traffic controllers to manage large numbers of airplanes.

Those opportunities have helped O’Neill cover his overhead and payroll, he said.

“We have always wanted to stay very platform-agnostic because if you have people on any range of devices, general consumers, we wanted to be able to target them,” he said.