Pin-and-Cross: A Unimanual Multitouch Technique Combining Static Touches with Crossing Selection

We define, explore, and demonstrate a new multitouch interaction space called "pin-and-cross." It combines one or more static touches ("pins") with another touch to cross a radial target, all performed with one hand. A formative study reveals pin-and-cross kinematic characteristics and evaluates fundamental performance and preference for target angles. These results are used to form design guidelines and recognition heuristics for pin-and-cross menus invoked with one and two pin fingers on first touch or after a drag. These guidelines are used to implement different pin-and-cross techniques. A controlled experiment compares a one finger pin-and-cross contextual menu to a Marking Menu and partial Pie Menu: pin-and-cross is just as accurate and 27% faster when invoked on a draggable object. A photo app demonstrates more pin-and-cross variations for extending two-finger scrolling, selecting modes while drawing, constraining two-finger transformations, and combining pin-and-cross with a Marking Menu.