You don’t have to spend money to play The Sims Mobile—but things move a lot faster if you’re doling out cash.

A new report from intelligence firm Sensor Tower reported The Sims Mobile players have thrown a ton of cash on the simulation mobile game. The Sims Mobile has earned more than $15 million in worldwide player spending in the first four months of its release. The Sims Mobile launched on March 6 for Android and iOS devices. It’s free-to-download, but there are plenty of ways to drop actual cash.

It’s a lot easier to just wait out actions when you’re starting out at the game, but as players progress there’s more of an incentive to spend. Whether it be for energy, SimCash, or tickets. Bundles of SimCash range from $5 for 250 SimCash all the way up to $100 for 7,500 in SimCash.

Sensor Tower said The Sims Mobile was publisher Electronic Arts’ eighth highest earner across the App Store and Google Play in June, with 59 percent of the mobile game’s revenue coming from the United States.

The Sims Mobile has a bit of competition from another The Sims mobile title, The Sims FreePlay—a seven-year-old title that was released in December 2011 for iOS devices. In June, The Sims FreePlay was EA’s third-highest earning mobile title. It doubled the revenue of The Sims Mobile, according to Sensor Tower. Developer Firemonkey Studios continues to support The Sims FreePlay with major updates, the latest of which adds pregnancy to the game.

The Sims was the highest selling PC game of all time when it originally released in 2000. The series has seen its fair share of saturation, but it and Pokémon proved there was a colossal audience for video games outside of conventional demographics. Now that mobile devices give everyone the chance to play, The Sims and Pokémon seem to be repeating history. The Sims Mobile has a long way to go to catch up to The Sims FreePlay, but $15 million isn’t chump change.