If you pay to be a developer for Google, you can publish as many apps as you want (to my knowledge). Apple developer account needs to be repurchased ever year for about $100 U.S. dollars, so there’s that too… yay for apple. But at least it’s as many apps as you want there too!
It’s highly encouraged that you only submit apps that you are proud of though. as they represent you and your name which could stand for a lot someday if this is what you want to aspire to make your living with.
Are you a mobile app development company or an individual? It is observed that the app store’s authority normally charged US$ 99. Besides, the complete process of uploading an app on IOS is depicted in the article mentioned by the @Again.