Listen
Listen to what I am saying: I have hundreds of apps. I use touch devices for a very long time. None of those apps show this behaviour of rotary knobs. Clearly you are the one that does not understand how touch works. Knobs should respond as faders. Vertically. Making circels on a touch screen is ridiiculous. A hand interfacting with a physical rotary knob does not even make a clock wise motion. Your knobs have issues. they jump from 40 to 100 and back because the design is flawed. You can't even adjust the cc knobs to a specific number. They will always jump to 2 or more. Try to set the knobs to CC 105 or CC 102 or CC01 Can you double tap to enter a value manually? Ofcourse not. Is it important to be able to set a specific CC? Yes. These are alpha stage issues. Do you need to hit save when you change the value of 1 knob? yes Every time. The amount of time it takes to design a interface will be more than you will ever win using it as a midi surface. Please design interfaces that show you understand how basic HCI and UX works. Do yourself a favor and pick a few basic operations a user will perform. Then apply the Keystroke Level Model. This will expose how bad iit is. It's your choice to have gazillion apps.Perhaps choose quality over quantity.