There are quite a few ways to make money from your game. Some of them are described in the following text.
First of all, the classical way is to sell your application at a fixed price. The customer pays once and then plays the game as long and as many times he/she wants.
The problem for you as a developer, in this case, is that you will lose a lot of sales due to piracy of the game. This problem even exists in the app stores and markets these days.
This is another method that is used for commercial games and for free games too. People pay a monthly/yearly subscription fee to be able to play the game or to get access to better features in the game. The subscription model ...