Since in-app purchases (iOS) often show higher conversions than those for in-app billing (Android), we will have a look at in-app purchases, in particular, using the case of the Empurror app.
See how in-app purchases can be implemented
The case of the Empurror
The Empurror is a little SpriteKit game for iOS that I have worked on previously. It is a very simple game about a cat (the Empurror) and many kittens, jumping off a roof. In this game, our hero (the player) needs to catch them all in order to succeed:
The game comes with three in-app purchases, all donations, not adding any special features to the game, other than a view of the Empurror saying thank you. Oh yeah, and you can rub his belly to make him purr.
Anyway,...