We’ve talked many times about how big mobile gaming has become, as well as how some companies have shifted their business entirely to the mobile realm (like, most recently, Kabam). However, according to a new report from the IDC, they’re a lot better than most people may have realized.

Gamesindustry International has reported that the study shows that the worldwide installed base for mobile devices, including both smartphones and tablets, has gone past one billion. This is counting devices that have been used for some form of gaming — quick or long sessions — for “at least once every three months.” And those numbers add up to a lot.

“Mobile gaming has rapidly emerged as the brightest star in the gaming universe,” said IDC’s research director of gaming, Lewis Ward. “The number of games downloaded to smartphones and tablets worldwide will nearly double to more than 60 billion games between 2014 and 2018. In this context, it will become increasingly difficult for the major handheld game console providers to compete effectively. The market as a whole will grow rapidly, though, and swing dramatically in the direction of Asia/Pacific and Android-based devices in particular by 2018.”

As you can see from the chart below, there’s been a big of growth over the years, but it’s could get even bigger in just a few years’ time, with a total of 60 billion worldwide in a span of four years.

IDC also explained that 44 percent of mobile devices used worldwide are now primarily used for gaming purposes. A big chunk of that is placed in North America, with over 157 million smartphones and tablets used to play games this year alone — that’s an eight percent increase over the previous year. In addition, around 48 million people paid for some form of game for 2014, totaling a revenue of around $4.8 billion.

When it comes to a defining leader, however, IDC believes that the Apple App Store has a lead over Google Play {link no longer active} “by a healthy margin,” despite the large growth of interest in Android devices.

And when it comes to popularity of devices, smartphones rule. “Since smartphones are far more ubiquitous than tablets, even though tablet gamers tend to more often pay for mobile games (tablet gamers have a higher ARPPU), over three-quarters of all mobile game revenue will still be generated on smartphones in North America this year,” Ward said.

Online multiplayer also plays a huge part in mobile gaming success, according to Ward — especially online role-playing adventures. “The time is ripe for mobile MOBAs. In 2015, we’re likely to see some breakout hits in this direction. The 4G LTE infrastructure is to the point that a critical mass of mobile MOBA gamers can form, and the latency is low enough that gamers on cellular can compete effectively against those playing on WiFi,” Ward explained. “One of the big barriers to mobile MOBAs, however, is the fact that multiplayer VOIP is hamstrung. It’s basically very tough to do live co-op games that leverage VOIP today, so this important, team-based aspect of MOBAs is practically missing from mobile environment. Part of the issue here in the U.S. is that there are 911 system integration issues to be worked out on smartphones (that of course don’t apply on PCs or consoles).

“There’s still every reason to believe that the sophistication of mobile games will take a big stride forward in 2015, and part of this evolution will be about delivering richer live, team-based interactions. The eSports phenomenon will spill over onto smartphones and tablets in 2015.”

Obviously, the growth will continue — and be quite impressive, at that.