How do you increase awareness of one of the world’s most popular video game series? Put it on a smartphone.

For two years in a row, both of Activision’s annual Call of Duty franchise entries — “Call of Duty: Modern Warfare” in 2019 and “Call of Duty: Black Ops Cold War” in 2020 — became the best-selling video game for the year of their release. The publisher further pumped up the franchise with the 2020 release of the free-to-play battle royale game “Call of Duty: Warzone,” which quickly amassed over 100 million players. And yet in some ways, these successes pale in comparison to those of the franchise entry designed for the smallest screens: “Call of Duty: Mobile.” This mobile title for iOS and Android has expanded the franchise’s global footprint in ways the already massively successful series has never seen.

“Call of Duty: Mobile” debuted Oct. 1, 2019, as a free-to-play game. That same day, it reached 1 million downloads. Nineteen days later, it had topped 100 million. That number swelled to 500 million in May 2021, Activision announced. By comparison, the franchise’s mainline entries, which have been steadily releasing since 2003, have sold over 400 million combined copies to date. While that’s a staggering sum for the premium versions on consoles and PCs — producing billions of dollars in revenue over the years — Activision’s relatively nascent mobile game has already generated over a billion dollars in revenue before the conclusion of its second year on the market.

Fueling its success is a combination of factors that includes the game’s strategic monetization model, the franchise’s preexisting popularity and the developer’s ability to deliver a comparable game experience on a widely accessible platform owned by billions of consumers worldwide.

Work began on bringing Call of Duty to the mobile market more than four years ago, said Chris Plummer, vice president of mobile at Activision. At that time, similar shooter-style games like “PlayerUnknown’s Battlegrounds” and “Fortnite” hadn’t yet released for mobile, leaving it an open question as to what a successful shooter game should look like on the platform. The developers dabbled with a number of potential ideas and designs for the game until other titles and technological improvements showed a mobile platform could support the ambitious vision they had in mind.

The end result is a version of the game that closely approximates the Call of Duty experience on console and PC, using touch screen controls to move the player’s character and aim their weapon. The controls are somewhat simplified, with an option for players to automatically fire at foes by placing them in their crosshairs, but the core experience plays very similarly to standard Call of Duty games.

Compressing a Call of Duty game — a franchise known for its massive, cinematic action sequences and competitive quick-twitch gunplay — onto a mobile device was made possible in part by a rapid acceleration in smartphone technology and processing power. Plummer also noted that players becoming more comfortable with in-depth, shooter-style games on mobile platforms provided the developers with the belief that they could achieve their vision. These days, “Call of Duty: Mobile” offers a number of the same experiences that the console and PC games provide: multiplayer gunfights in real time; a version of the franchise’s popular zombie mode that pits players against waves of the undead; and a last-player-standing battle royale held on a sprawling map.

“We adapted the game to, frankly, just be much more on brand and much more on point as a real Call of Duty immersive experience that puts you right there on the front lines of it,” Plummer said. “And the more it became closer to the Call of Duty core, the more it started to really come alive as the game you see today.”

One of the key decisions that fueled the game’s success was making it free to download and play. The tactic, utilized by a number of other mobile games including “Fortnite,” removes a potential barrier for users who aren’t sure they want to spend money on a game they may not like. Some mobile titles have developed a reputation of being free to play but also “pay to win,” requiring players to spend money if they want to prevail when competing against the game’s AI or other live players. “Call of Duty: Mobile” allows players to unlock new weapons and improve their abilities simply by playing the game, though paying real money can aid with leveling up their characters more quickly.

“It’s ultimately a free-to-play game and a fair-to-play game, which means we don’t force anyone to spend money,” Plummer said. “We have to earn that. And we earn that just by delivering a great game with the kind of content that they really want, but it’s their option. You can play Call of Duty without spending a dime. And we know that if we do well with that player and we continue to entertain them, then eventually they’ll want to buy something. And that’s great for all of us.”

As evidenced with the game’s half-a-billion downloads, the free-to-play plan succeeded in rapidly bringing new players into “Call of Duty: Mobile.”

“With ‘Call of Duty: Mobile,' the game was able to reach audiences at the global scale more rapidly than their console and PC counterparts,” said Lexi Sydow, head of marketing insights at mobile data and analytics provider App Annie. Sydow attributed the rapid user acquisition in part to the relative affordability and accessibility of smartphones around the world compared to gaming consoles and high-performance personal computers.

Michael Pachter, a research analyst who specializes in the video game industry for Wedbush Securities, estimated the market for Call of Duty’s console and PC games at about 650 million potential users worldwide. By breaking into the mobile market, Pachter believes Call of Duty’s potential userbase jumps to some 2.5 billion users by including smartphone players.

Those new players have already paid dividends and could benefit Activision even beyond in-game spending, which according to Activision Blizzard’s second-quarter earnings report is on track to top $1 billion in consumer spending for 2021. Since launch, it has been the top-grossing app on either app store (Apple or Google) for at least one day in 95 countries, according to App Annie’s data. The massive increase in players newly introduced to the world of Call of Duty could also have a reciprocal effect, boosting sales of the mainline console and PC games. The next such game, “Call of Duty: Vanguard,” releases Nov. 5.

“That has to expand the market for the premium version of the game,” Pachter said.

For all of this early success, Plummer believes the current mobile game merely represents a starting point.

“We’re really just scratching the surface,” Plummer said. “This is like the current-gen state of the art. And we’re also thinking about the future and like how all this learning applies to where we take this into the future and what the next generation experience is going to look like.”

To that end, the company is significantly adding to its mobile game development teams.

“We’ve grown our staff more than five times since launch,” said Matt Lewis, VP of product for “Call of Duty: Mobile.” Lewis noted that the studio is still hiring, and he expects more growth for the mobile division over the next year.

Activision Blizzard is currently facing a lawsuit from the California Department of Fair Employment and Housing, which alleges that a number of women working throughout the game publisher’s network of development studios faced widespread harassment, were denied opportunities to advance and were paid less than their male counterparts. Earlier this month, an Activision Blizzard employee posted on Twitter saying a recruiter for the company had contacted her saying that articles she was sharing about the company amid the lawsuit “freak candidates out.”

Through a spokesman, Activision Blizzard responded to a question about whether the lawsuit had impacted its recruitment efforts for the mobile game, writing in an email: “Our recruiting for ‘Call of Duty: Mobile’ continues to be healthy, and we are actively growing with our expansion toward new projects, which will include the creation of a new studio team as well as increasing our head count across several studios.”

Given the success of “Call of Duty: Mobile” and rising interest in mobile markets throughout the video game industry, Pachter believes a model similar to that of Call of Duty will be applied to Activision Blizzard’s other major franchises in the years ahead.

“The real key is to have a comprehensive offering across multiple platforms for each big brand, so we expect to see this model adopted by ‘Diablo’ [which is currently in development], then ‘StarCraft’ and ‘Warcraft,’" Pachter said.

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