Production cost of apps

When you upload an app you get 70% of whatever the customer pays. So the only way to get Apple to pay you for each download would be to charge for it. Apple doesn't get paid when someone downloads a free app so you don't get paid either.

Developers typically make money on free apps using either an ad supported or freemium model. Some apps even use both. The app itself is free but you install ads in it and get paid for each ad impression. Others bundle in-app purchases where you can enhance the app somehow if you buy something within the app. You need a very popular app in order for either of these methods to pay off.

Depending upon the size of the company it has been suggested that freelance app developers gain anything from 6,000 to 20,000 depending upon the scale of the company. Obviously as apple have their own designers/coders this may be cut in price as the coders are working for a annual price.