Examples of Payment models

There are no limits to what you can and cannot charge for in your game, but we have some examples of models that we think can work really well depending on your game:

Trial to purchase

If you've made a big quality game that you think people would want to pay for playing, then you can make a small part of it free to play for everyone, and require payment to unlock the entire game. If you can make the free part as compelling and fun as possible, chances are high that people would pay to play all of it. This model works best for linear games where a player is progressing through levels, and you can choose at what point they have to pay to continue.

Extra levels and maps

Another models that probably works best for puzzle games and similar is selling individual levels or level packs. You could make different kinds of levels that you charge for, and let the user decide which kind they want to purchase if they want more than whatever puzzles and levels you give out for free.

In-game features or advantages

Something that probably works best in multiplayer games is to sell in-game advantages or features that help the players that purchase them to win against other players. Depending on your game, it can be simple things that make the player faster, better or stronger. Also remember to make players that have purchased items stand out more so they can show off their support for the game to all the other players. With this model you can make lots of small items that you sell, instead of just one big item like the previous models.

Donations

Finally, if you have a solid game with regular players that really like you and your game, and you don't want to require people to pay to play, you can always use the payment system to ask for donations. Just set up a few different size donation items for your game, and remember to always thank the players that have donated.