I've never been a fan of the 'games as art' philosophy. A game is good because it contains good game features - enjoyable controls, logical level progression, intuitive flow - not because it attempts synaesthesia or the like.

Hence, if Rez, Braid, Ico, Lumines, and so on are games worthy of our attention, it's not because of their aesthetic sensibilities: it's because they're fun. The aesthetic discussion comes second.

It's no surprise, then, that I don't think Auditorium - a game in which you deflect a flow of coloured particles to complete musical compositions - is art, although I'm sure plenty of people will argue that it is.

Perhaps what's more significant is Auditorium doesn't easily fit within the rules of gaming, either. It has some of the necessary properties, but it uses them in a fairly lacklustre manner.

What's important, however, is that Auditorium is a beautiful experience - on iPhone, only Zen Bound comes close in terms of aesthetic impact.

The basic tones

Each of the game's 25 levels, split between five musical themes in a contemporary classical style, starts in silence. Scattered around the screen are various items you use to complete the stage.

There's always the particle flow of course, one or more fixed containers which have to be filled up with particles to trigger the music. Additionally, you're given movable icons that influence the particles' flow in some way, such as shifting it left or right, accelerating it, or making it trace a figure-eight shape.

Four of the game's musical themes involve colour, with the initial white particle flow changing colour as you force it through various colour-changing circles. These correspond with the colours of the containers, which can only be filled by a matching colour flow.

The orchestration

But as the name suggests, Auditorium is about music. Each container effectively acts as a sampler, so when it's filled up you hear a part of the composition. The volume is controlled by how full the container is.

The goal of a level is to fill up each container with a particle flow of the correct colour to complete the music. Yet the enjoyment of Auditorium is triggered less by such completion than the experimental process that builds up to it.

The main reason is there's no defined way to solve each level, much less a timer to beat, or high score points for elegant solutions. Everything is literally free form.

For example, you can complete many levels by just carefully moving around the figure-eight icon to dynamically change the particle flow until you manage to fill up the containers. Neatly, when one container is full, it will stay full for a second or so even if it's no longer in the particle flow, enabling you to quickly spray particles around the screen.

In this way, Auditorium counts as a puzzle game only in the loosest sense. Instead, the player gains more enjoyment by prolonging their failure to finish the set goal than satisfying it.

The journey, not the destination

Still, once you've finished each level, the final particle flow remains on the screen alongside the music, not unlike a beautiful screensaver. At the end of each of the five themes, you can even play around with their constituent samples.

Indeed, the only disappointment with Auditorium is its longevity. Even playing without urgency, it's hard to stretch the 25 levels out past two hours, while the option of three musical packs - each 99c/59p - feels somewhat commercial.

Incidentally, there are five free levels in the Lite version [Link] for those unsure of the $2.99/€2.59/£1.79 cost, or you can try out the web-based Flash version.

Whatever you decide to pay, Auditorium is well worth the price. It's not art and it might not even be a game, but in parts it approaches sheer joy.