I’d love to know where the money is going. I suspect the largest single category is the various video services (Netflix, HBO, Showtime, etc.). I worry the second largest category (based on seeing television ads for the games) is for “virtual coins” so you can be successful in freemium games.
My experience as a (hobbyist) developer writing productivity apps (for a niche market) and seeing various apps that aren’t sustainable Transmit for iOS is that most productivity/utility apps don’t generate much income. I averaged less than $10 a day in total sales from a couple iOS apps and one Mac app in 2017. I suspect with some marketing, switching to a freemium model so you could try the apps before purchasing them, and more effort in improving those apps (localization, etc.), I could increase that to $50 to a day, but I doubt I could make enough to quit my day job.
There are, of course, exceptions as I assume OmniGroup must make a reasonable amount of money from their iOS apps and a few indie developers make a reasonable living from the App Store (although @manton and @danielpunkass and others supplement it with podcast advertising and other sources of income).
I worry that a large portion of the $100 million a day being spent in the App Store is on consumable virtual coins and that doesn’t seem healthy to me.