GarageBand for iPad: The Matrix as Interface

The Drums tool in GarageBand for iPad includes a beautiful new interface that I think has potential as a design pattern for many different kinds of information access and organization.  It is a matrix of 2 scales: simple to complex and quiet to loud.  Instruments can be dragged into the squares on the matrix from the left, or the die on the right will assign instruments across the matrix.  The play button then plays the instruments together, using the matrix as a guide. 

1.  It solves the difficulty of intersecting attributes.  Right now, on most interfaces, this same functionality is accomplished with dropdown choices or a couple of sliding scales.  People can adjust these widgets, but it isn't as easy, and the intersection is in the head of the user - there isn't a representation of it on the screen.

2.  It is easy to 'play' with.  This is actually a complex multi-step set of decision points combined into one screen.  If these were separate pages in a workflow, the time it would take to 'explore' and lack of immediate result would discourage the user from trying different combinations.

3. It doesn't force numbers on people.  I think that many (non-programmer) people carry around a lot of number-fear.  They get intimidated by them, and are sure that there is one correct option in every number set.  Sure, behind every programmatic decision, at some level, is a number.  But users don't see them here, don't need to know them, and (heresy?) don't care.  They are interested in the intersection of the matrix onto which the instrument is placed, not the individual values that intersection represents.  'Hiding' the numbers does some key things, from an interaction standpoint: 

• it declutters the screen, focusing on outcomes not inputs
• it focuses on the intersection of the two continua, not on the numbers behind them
• it prevents non-mathematical people from being intimidated or turned off
• it encourages change, celebrating data malleability, not stasis

Since my background is in interfaces for presenting complex data sets like medical diagnosis or pharmaceutical information, my mind was immediately drawn to this interface as a tool in a decision-making matrix for those applications.  For example, if I were trying to define a set of diagnosis data, I could set one axis as Layperson > Senior Clinician (Simple > Complex) and another as stage of diagnosis (Differential Diagnosis > Ongoing Treatment) I could control the subset of disease information to see.  Maybe my patient can handle a more complicated document,  but I am still testing for the diagnosis, so I want to provide information at the middle of my matrix.  Or maybe my patient's literacy level is low, but they've had the diagnosis for a while and just want to see what's new about it.  So I can select a simple document, but one that is centered on ongoing treatment.  I can use the matrix as a focus knob on my data, homing in on the right cross-section for the circumstance.

As our information overload becomes more extreme, we have to look at ways to simplify, clarify, and focus the information we send and receive.  We can't process it all, and we can't be responsible for manipulating the data to suit the circumstance each time we retrieve it.  We also need to give users of data (audio, textual, or visual) the ability to change and toy with with their perspective on it.  Our most important mission becomes the presentation of the data for analysis, and we can learn from these fun and playful applications what is worth testing in other situations.