It's one thing to make an app, it's an entirely different thing to get it through the App Store review process. Did that guy's app make it on the App Store? He

It's one thing to make an app, it's an entirely different thing to get it through the App Store review process. Did that guy's app make it on the App Store? He could have easily built it with private APIs which would work but wouldn't pass review (maybe, App Review is very inconsistent) or many other reasons why he could and Spotify couldn't.