Interface design for an app aimed at guitarists -- now that must be an interesting challenge. You're tempted to improve the interface presented by actual hardware, but your user group is notoriously conservative. They aren't like many users of computer programs, in that they don't appreciate the same things about an interface. They don't even want to know the word "interface"; they just want to be able to do what they did before, only with this new thing instead of the old thing.
They can't be blamed for that attitude, and I doubt there's any point trying to change their minds about it. One huge reason that justifies their conservative approach to interfaces: a player must be able to get the same sound he used on song "whatever". Having a new whizbang toy is great, but if he can't play song "whatever" with the same sound, etc., as before, then the new whizbang thing has become 100% useless.
Likewise, the knobs and switches that constitute the interface, for a guitarist who uses a certain distortion pedal or echo machine, become part of the player's instrument -- the interface is now part of what the musician "plays", along with the strings and knobs on the guitar. Take those away, and you've taken an astonishing step backward, as far as performing musicians are concerned.
I realize that showing knobs on the screen is not great interface design from the viewpoints common among software designers, but it's essential for guitarists, and it's not even enough. What would really help is something like the Microsoft Surface, except with actual knobs and switches. I'm not even sure that would help enough to matter. The best compromise is probably what we see here, what I like to call "the Reason rack" interface. It drives me crazy sometimes, but I understand that it makes more sense to more musicians, and that I'm in the minority of users where that preference is concerned.
