Why not finally adapt the JQuery UI to Multi-Touch? I would like to propose the development of a second-generation JQuery UI. I would like to offer support for Pointer Events as a basis. For example, add a pointerId to draggable which interacts at the moment. And in general to implement simultaneous interaction with multiple devices and fingers. You have to start with JQuery 4. On the other hand there is another no less interesting suggestion. This is to use CSS variables. This would allow you to customize the corresponding styles.