[What can you learn about game design from working on mobile titles? Cellphone game design veteran Ventrice (Guitar Hero Mobile), now working with iPhone developer Smule (Ocarina/Leaf Trombone) on music games, discusses the key conceptual layers of game building that are common to all titles.]

A salesperson might understand the importance of a compelling brand but have no concept of game mechanics. An engineer might understand a compelling game mechanic but not understand the methods of teaching it to the user.

Creating a successful game requires critical cross-discipline coordination, yet all too often team members only understand the facets of the design that face their own specializations.

It is the responsibility of the game designer to bring these specialized perspectives together in a comprehensive design. If the designer fails, different groups in the team will waste time and effort working towards unrelated goals.

But bringing together aspects as disparate as the marketing face of a game and its user interface may seem to be an undertaking in the abstract. What is needed is a framework for understanding the interconnectedness of a design; a way to visualize the trickle-down (or up) impact of design decisions made at any level.

Mobile Insight

Mobile phone games may not be as immersive or as intense as their console and PC counterparts, but their simplicity provides an ideal starting point to an inquiry into the structure of game design. The mobile platform is unique for two reasons: reduced depth and increased breadth.

Reduced Depth. You've probably heard that a design is perfect once everything that can be removed has been. The mobile platform puts this adage to the test. Even today, in the dawning age of the iPhone, mobile developers still have to deal with phones that allow as little as 128k of space; that's 128k for art, code, game data, sound and anything else.

These limitations nearly prevent any kind of gameplay from existing at all, but games do survive; very simple games. In these stripped down games, the underlying design structure is highly refined and clearly visible.

Increased Breadth. Over the course of a relatively compacted span of time, a mobile designer works on dozens of titles, spanning nearly every conceivable genre.

Designing three or four different games at a time, you have two options: learn to understand all games by a common set of terms, or go crazy trying to keep track of everything individually.

What follows is a summary of lessons learned in the field of mobile design.

The Layers

Every game design can be understood through four distinct perspectives. These perspectives stack nicely, so it is convenient to label them as the four layers of a design:

• Concept
• Paradigm
• Mechanics
• Interface

As an example, let's take a quick look at the perennial mobile favorite, Tetris, in Figure 1:

Paradigms may seem abstract at first, but they are an essential perspective to understand.

• Concept:
  
  The concept is almost too simple; Match sets of blocks to clear away a growing pile-up of debris.

• Paradigms:
  
  The paradigms are the "frames of mind" the player is asked to use while playing. The "geometric spatial relations" paradigm listed here is simply describing the variety of visual puzzle the user will be engaged in; other example games in this paradigm are jigsaw puzzles, Rubik's cube, Echochrome, Lumines, Peggle, etc. The "set-building" paradigm listed here is often known as "match-3" in games such as Bejeweled, Lumines, Chuzzle, Hexic, etc.

• Mechanics:
  
  This section is organized by Features. Features are the game requirements needed to support the paradigms.
  
  Mechanics are the substance of this layer; the parts that the features are built from. There are too many mechanics in this example to illustrate all of them and some omissions include: "Game ends when pieces are blocked from entering the play area", as well as explanations of the verbs: "settle" and "contact".

• Interface:
  
  As you can see, not every mechanic needs direct user input. In a well-designed game, the interface is minimal but causes chain reactions across mechanics. For example, here the user's ability to affect the dropping of blocks causes blocks to contact in different places, resulting in rows either being completed or not.

Every game can be defined by these four layers. Let's take a more detailed look at each individually.