Yeah, except he himself described the first app as "simple" and the next 9 apps after the first consisted of nothing more than changing the YouTube channel id the app pointed to and changing the app's name.
$50,000 seems pretty exorbitant for a "simple" app that does nothing more than embed YouTube videos.
$50,000 for the literally 5 minutes of work involved in changing the channel ID and app name is downright comical.
There's no way to spin this as $500,000 worth of work. I don't care what his billing rates are. (And I suspect his billing rates aren't very high to begin with — he doesn't strike me as the sharpest tool in the shed.)