China's mobile games market reached $7 billion with 1 billion players in 2015, states a report from NewZoo and TalkingData. Although at a slowing rate, mobile games are still growing in the vast country. As the largest mobile games market continues to grow, the biggest developers face increased competition to attract new users who will pay and play for an extended period of time.

The growth rate of mobile games devices in China dropped from 10.9 percent in the last three months of 2014 to 4.8 percent for the last quarter of 2015. During that time, 200 million mobile game devices were activated with a billion users by the end of 2015. Sales grew 57 percent year over year to $7.1 billion. It's projected that the mobile games market will reach $13.9 billion — accounting for 48 percent of the entire games industry in China — by 2019.

Casual and card games were the most popular genres for mobile players, but more developers are looking to role playing games and action titles, described as heavy content games, as a way to increase revenue. There is a cost to heavy content games, including more time spent on the research and development of the title along with increased marketing. Because of this increased spending, smaller developers are finding it harder to compete with larger companies.

Tencent, a company with a $200 billion market cap, has multiple investments in the industry. It has full ownership of Riot Games, developers of "League of Legends," along with investments in Epic Games, Activision Blizzard and Glu Mobile. Tencent has three games — "Parkour Everyday," "Craz3 Match" and "Rhythm Master" — in China's top 10 casual games in terms of coverage on Android devices. "We Fire" is the top action game, while "King of Glory" is the top strategy game. Tencent maintains similar dominance in casino mobile games with "Fight the Landlord," Mahjong," "QQ Chinese Chess" and "Happy Bull" in the top 10 in terms of coverage.

Happy Elements is another company succeeding in the competitive Chinese mobile games market. The company's casual games, including "HappyFish" and "Anipop," are installed in 15.22 percent of Android phones in China, according to NewZoo. Other competitors include Netease ("Fantasy Westward Journey"),  Shanda Games and Perfect World.

These big players are exploring new ways to add revenue, with eSports being a key genre to attract new users. "King of Glory," "DOTA Legend," "Fantasy Westward Journey 2" and Blizzard's "Hearthstone" are among the top grossing eSports titles in 2015. Movie crossovers, along with licensed cartoon and comic properties, are other genres being targeted in the race for new users.