4 years later, and 'Pokémon Go' players have spent nearly $4 billion on the wildly popular smartphone game

• Just over four years ago, "Pokémon Go" launched for smartphones and sparked a worldwide phenomenon.
• With tens of millions of players around the world, "Pokémon Go" has been a smash-hit success: Players have spent nearly $4 billion on the game across the last four years, according to Sensor Tower data.
• As the years have gone on, player spending has actually increased — 2019 was the game's biggest year since launch, with nearly $1 billion spent.

In July 2016, "Pokémon Go" sparked a worldwide event: Millions of people all over the world were suddenly outside in droves, capturing Pokémon.

As the years have gone on, that all-encompassing level of interest has dissipated. But millions of people are still actively playing "Pokémon Go," and those millions of players have continued spending money on the free-to-play smartphone game.

As of this July, "Pokémon Go" players have spent nearly approximately $3.6 billion, according to mobile analytics firm Sensor Tower.

Perhaps more impressive: 2019 was the game's biggest year yet with just shy of $1 billion spent.

Despite costing nothing to play, "Pokémon Go" makes money by charging players for in-game items. Those items can be earned by playing the game, but some players instead choose to purchase them with real money.

It's those optional purchases that drove nearly $4 billion in sales across the last four years — players buying Poké balls, and other consumable items.

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