Taking a bulletpoint approach to the F2P Summit, Gamesbrief's Nicholas Lovell burst through his 15 Basic Rules of F2P.

It's part of an ongoing series running at www.gamesbrief.com/rules

1. Make it fun

We're making games. There maybe different definitions of fun, but games need to be fun, even F2P games.

2. The Starbucks test

Games need to be snackable. Can you have game session while you're in a queue for coffee?

Good examples are CSR Racing, Infinity Blade, Bejeweled Blitz and Tiny Towers.

3. Is there also depth?

While players should be able to play for a minute, they should also be able to play for an hour.

4. Complexity in layers

Like a Pixar movie, appeal to different audiences. A good example is Jetpack Joyride. There are specific achievements, but there are other ways to play, which in this case involve the tension between collecting coins and trying to stay alive for as long as possible.

Other options can include beating your friends' high scores. Another example is Temple Run.

5. Evergreen

Your game must never end. F2P games are all about getting people into the funnel and once you get people into the funnel (i.e. playing your game) you must keep them there for as long as possible and that means replayability or endless gameplay.

6. Be generous

Playing off the '0, 1, 100 rule', you need to give away a lot of game ('the 0'), as well as rewarding those people who pay you a little ('the 1') and a lot ('the 100').

7. Be free forever

Paywalls are bad. A timed trial or a demo mode isn't being generous. The most expensive thing in F2P gaming is about getting players, not making the game, so don't annoy your players.

8. The $1 no-brainer

To get players to buy some IAP - your #1 objective - you need to make their first purchase absolutely brilliant.

Again Jetpack Joyride does this well with its counterfeit coin maker, which doubles your progress through the game.

9. And the big spender...

But once someone has spent $1, you need to get them to spend more. This is Lovell's '100', but it can be anything from $20, to $100 to $1,000.

This is reflected in research that says that the average single IAP transactions in the US during 2011 was $14.

10. Pizzazz, not polish

Despite the slightly confusing terminology, Lovell argues that F2P games should be focused on exciting players in terms of rewards and progression, not beautiful graphics ('console-style') for their own sake.

(The confusion occurs as many F2P developers talk a lot about 'polish', when they're talking about rewards.)

11. Kill the tutorial

The first few minutes of a games are important so you need to get the player invested in the experience.

12. Don't kill the player

You should never 'lose' in a F2P game. The game experience should never tell you that 'You Suck'. Getting players is hard so don't annoy them. This can be as subtle as replacing a 'Game Over' message, with a 'Well Done' status message at the end of the game session.

13. Sell emotions, not content

We're not selling content. We're selling the experience, the self-expression of wearing a funny hat, high score leaderboard placement, gifting etc. We're in the business of emotions.

14. No one knows the answers now

The F2P business is changing so quickly that no one knows the answers all the time.

You need to experiment, but you need to know what answers you're looking for - with metrics. Also, experiment at a low risk, not a single-shot, all-in experiment. And when you have success, iterate and do it all over again.

15. It's never done

You're providing a service. Your game is never done.