A report has been prepared by Sensor Tower website which states the above. According to it, revenue generated per U.S. iPhone grew 36 % between 2017 and 2018. This means that, while the average iPhone user spent $58 on apps in 2017, the same user spent $79 on them in 2018. Reportedly more than a half of this revenue has been spent on mobile gaming; much of the rest of increase is due to subscription-based apps.