Hi,
Thank you very much for the suggestion.
Regarding the possibility of using the Auto Reset Knob as a Pitch Bend, that is an interesting idea, and we will certainly keep it in mind.
As for adding a linear control mode using vertical movement, we understand the idea, but we believe it presents several usability challenges in a touch interface.
The first issue is the position of the knob on the screen. If the control is close to the top or bottom edge, vertical movement becomes limited because the finger can quickly reach the edge of the screen and lose contact with the surface. One possible approach would be to change the gesture axis and use horizontal movement depending on the knob's position, but this does not completely solve the problem either. If the knob is in a corner, for example, we would need to use yet another type of interaction, such as circular movement.
This would mean that the same type of knob could require different ways of interacting with it depending on where it is located: vertical, horizontal, or circular. Although this could technically be implemented, from a usability perspective we feel it would be a nightmare, as the user would have to learn and remember different behaviors for the same type of control.
There is also another important issue with touch interaction. If, during a linear movement, the finger accidentally loses contact with the surface and then touches the screen again, that new contact could occur in a different position, potentially even on a button or another control adjacent to the knob. This could trigger an unintended action.
For these reasons, the current circular behavior has the advantage of providing a much more consistent interaction: the user can manipulate the knob without depending on the direction in which the finger can physically move or on the position of the control on the screen.
In any case, we really appreciate the suggestion and will keep it in mind for future improvements.
Many thanks!