Yes – what this ultimately comes down to is the question of malleability of interface versus specificity of interface. Capacitive touch screens offer an incred

Yes – what this ultimately comes down to is the question of malleability of interface versus specificity of interface. Capacitive touch screens offer an incredible amount of malleability compared to what we're used to in the history of user interfaces. Within two dimensions, there's simply no limit to what we can do with them. They can be reconfigured infinitely, and yet that infinity is of a low cardinality compared to the infinite number of possible user interfaces. This difference in cardinality tricks us into thinking it can do anything. As you say, there are still many applications for which purpose-built interfaces are vastly preferable. Until some sort of science-fiction nano-structure can increase the cardinality of the solution space, the application of malleable interfaces will have distinct limits.