Even before its acquisition by Activision Blizzard, King Digital was the world’s largest mobile games developer, thanks to the phenomenal success of the Candy Crush franchise. So, it’s no surprise that the company knows what motivates players to purchase items from a free-to-play game. It’s down to a science.

Michele Airoldi, business manager at King Digital, will be speaking at this year’s GDC in a session titled, “To Buy or Not to Buy” — where he will discuss the factors that lead-up to purchasing in-game items so that developers can better build a successful game economy using “a new and simple purchase decision model based on the interplay of the product, the offer and the player.”

[a]listdaily talks to Airoldi about some of what will be covered at the GDC session and the nature of in-app purchasing decisions.

Michele ArioldiSpending money on a free-to-play game might sound like a contradiction to some people. What is your response to that?

All of our games at King are free to download and play, and they are designed to provide our players with some light entertainment when they have a few minutes’ spare.

I think that the huge growth and success of the free-to-play model shows that the vast majority of players accept and like it. In order for us to build and maintain a good relationship with our players, it’s essential that we continue to make games that are fun and engaging to play, and accessible to anyone, anywhere. It is not essential for our players to buy items in order to progress through the game.

What kinds of premium content do players generally prefer?

The types of content we offer our players generally depends on the genre of game but as the majority of our offering is casual puzzle games, we tend to sell boosters and gold bars, which players love as you can use them to buy lives and help you on some of our trickier levels.

We also released our first resource management game last year called Paradise Bay, and players can choose to spend to speed up tasks, as well as purchase cosmetic items to customize their island.

How do you present paid content without disrupting the game?

We always want to make sure that the player has the best possible experience every time they open and play one of our games. So that we don’t disrupt the game in any way, we only show players the items they need when they need them, separate from the game play.

For example, the player has to purposely click into the Gold Bar shop in order to see it. A player will also be given the option to use or buy gold bars if they have failed a level and need additional lives.

Does King have to invest heavily to promote paid content, or are dedicated players naturally drawn to it?

As I mentioned, the player experience is what is most important to us when we are thinking about designing or releasing a new game. Carefully thinking about the experience from start to finish and avoiding disrupting the player is key.

Promoting paid content aggressively would go against their preference and, ultimately, our interest and so we prefer to invest more in understanding what our players want and need. From this we can see that engaged and dedicated players understand our offers and are naturally drawn to them.

Does premium content have to be tailored to a specific game, or will an item that works well with Candy Crush Saga work equally well with a different game?

Before and after we release a game, our teams conduct a series of tests to find out what people like or dislike so that we can offer our players exactly what they want.

As I spoke about before, our premium content offering in the puzzle games tends to consist of boosters and gold bars, which have proved hugely popular with our players over the years. However, the type of booster or power-up we sell will change depending on the game.

We recently launched a new booster in Candy Crush Jelly Saga, the third game in the Candy Crush franchise, which was an evolution of the very popular lollipop hammer from Candy Crush Soda Saga.

We are very data-driven and we closely monitor our metrics to tune our offer to our player in the best possible way.

What is the most important thing to keep in mind when developing premium game content?

The most important thing to bear in mind when developing premium game content is thinking outside the obvious “functional product” categories and focusing more on how to integrate the content into the user experience. In our industry it’s not so much ‘what’ you sell that matters, but ‘how’ you do.

At King, we take into account that our player making a special and important decision when purchasing one of our products, and the context for doing so is very different from simply buying groceries in a supermarket or a book online.