The revenue earned by iOS app developers has reached $86 billion. $890 million of that was over a 7 day span in 2017 from Christmas Eve to New Year's Eve. This number is not only from paid apps, it includes in-app purchases. That number does not, however, include revenue from advertising. Since the App Store's debut in 2008, growth has been exponential. "Apple paid out $26.5 billion of that sum in calendar 2017 alone. That's 31% of the almost decade-old App Store's payouts in just one year." The total revenue will likely hit the $100 billion mark sometime this year, possibly even in the next six months.