The global mobile gaming market could grow from $56 billion in revenue in 2017 to $106.4 billion in 2021, according to a recent report by Newzoo and Arm. That would represent 59% of the entire video game market by 2021, compared to 46% last year.

Chart showing estimated annual revenue from mobile games, 2017 to 2021.

Data source: Newzoo and ARM. Chart by author.

With 577.9 million mobile gamers, China is the largest mobile gaming market in the world. However, the growth of China's gaming market could be throttled by tighter regulations over game approvals and play time limits for minors.

The top company to watch in mobile games is Tencent (OTC:TCEHY), the world's biggest video game publisher. Six of China's top 10 grossing iOS games are published by Tencent, according to App Annie.

Tencent holds a 40% stake in Epic Games, which publishes Fortnite, and a majority stake in Supercell, the maker of Clash of Clans. App Annie ranks mobile Fortnite and Clash of Clans as the two highest-grossing iOS games in the U.S.

Newzoo also expects more demanding mobile games to boost sales of high-end smartphones. As of June, the market researcher reports, there were 1 billion "high-end active smartphones globally," an increase of 76% year over year.