Since their release, the usefulness of smartwatches has been arguably hampered by their tiny screen size. One possible solution? Transforming the surface around a smartwatch (or a smartphone) into a larger input field using sonar.
Researchers at the University of Washington have developed such a tool, called FingerIO. FingerIO uses sonar to track two-dimensional finger movement to within 8 millimeters. Since the input surface—like a table, or a forearm—is now larger, making fine manipulations on a small screen is easier to do.