Choose Files with this lightweight file chooser. Which provides many features for single selection multiple selection.
This is a simple Seek Bar, in the shape of a circle, responsive to the speed of the spin: the faster you spin the control, the faster the progress increases.
Very much in the style of old iPods, this is a very intuitive control when a value from a variable range has to be chosen, and for wearable apps. It has been used in a production app for a while now, so it is well proven.