Apple's App Store just had its best month ever - and it's probably because of Pokemon

Summer's here, school's out, and people are downloading and paying for apps on their iPhones. 

Apple CEO Tim Cook announced on Wednesday that the company had set a record for total billings and amount paid to developers for the iTunes App Store in July.

"App Store developers have now earned over $50 billion! Congratulations on your success and such inspired creativity. July was a record-breaker for the @AppStore! Highest-ever monthly billings and money paid to developers," Cook wrote on Twitter. 

One reason why the App Store might have had a banner month is Pokémon Go, the mobile phenomenon that much of the world has been playing all month.

Pokémon Go generates money through in-app purchases, of which Apple takes 30%, 

Apple said that Pokémon Go set a new App Store record for first-week downloads on iPhones and iPads. And last week, CEO Tim Cook said that "in terms of [augmented reality] and the Pokémon phenomenon, it's incredible what happened there."

One estimate from investment bank Needham suggests that Apple could possibly book $3 billion over the next two years, thanks to Pokémon Go. And it appears that the sensation is already having an impact on Apple's top line - at least in its services division. 

Apple has signaled that it is emphasizing the App Store as an increasingly important part of its business. In December, Apple put Phil Schiller, its head of marketing and one of Steve Jobs' top lieutenants, in charge of the App Store.