The first talk at GDC Europe 2011 about mobile games came from Oscar Clark, the evangelist for Chinese-focused Android-concentrated social network PapayaMobile.

"It's not rocket science," Clark kicked off. "But these are useful things to think about when it comes to mobile game design."

Before, starting on his points, he also pointed out that a social game is a game with people you have a shared, social experience with.

"The hardcore say social games means less game, but this isn't necessarily the case," he said.

1. Games as a service

Your game needs to evolve. You need to look at player data to see in which ways they want it to evolve.

2. Look at the reward behaviour

Based on Bartle types, different players need different rewards. There are Collectors (what items are they collecting), Explorers (exploring what, where are they going?), Socialisers (socialising with who?) and Competitors (only one person can be no.1).

3. It's not a free lunch!

100: 10: 1 rule. Free, paid and whales all need to have a great time in your game, no matter how they play it. This means the things people buy with money, need to make the game better for those who buy them.

4. Feed the Habit

Why should people want to come back to your game? Daily challenges, leaderboards, achievements, all built excitement in the game.

5. Social achievement

Why are achievements relevant to players? Usually there's a social element, because you're showing them off to others. Gifting can be another very important way to creating a language - social glue - between players.

6. Time versus Money

Buying things should make my game better, but you can't break the game for the non-paying audience.

7. Consumable goods

What is the elasticity of demand? When you change the price of your items, how does it affect the money you generate? Low cost items are low risk for new users, and then you tempt them with better value, high cost bundles.

Especially on Android, you have to encourage people to put their credit card into Google Checkout for the first time.

8. Scissor: Paper: Stone

Players need to make meaningful choices: dilemma is a great way of maintaining game balance. Ambiguity in gameplay drives community interaction because it leaves room for debate. You can use virtual goods to add new choices to the game.

9. Playing metagames

Your game can be more than the game. You can use ideas of metagaming such as leaderboards or the interactions between players to drive more activity.

10. It's my game!

Once you release a game, it's not your game any more. You have to be flexible in terms of what your audience want's do with the game it's playing. Let gameplay emerge in terms of how users are sharing their own stories through your gameplay.

Conclusion

Communities are the important thing about social games, so you need to think carefully about how you engage your players, enabling them to create new communities as well as bring in their existing community.

"Mobile is particular well suited to social because of the way people quickly drop in and out of the experience," Clark said. "It's social dim sum."