DeLightTouch: Light sensor assisted multi-touch gestures on unmodified commodity smartwatches

Using a small touchscreen on a commercial smartwatch is often a hassle. It is easy to make selection errors on small touch-screens and multi-touch features are rarely supported. To overcome these limitations of current smartwatches' user interface and user experience, we design and develop DeLightTouch, which is a lucid input method using a light sensor to enable multi-touch gestures on smartwatches. By using a built-in and readily available light sensor in commodity smartwatches, we can easily enrich input expressivity of the smartwatch without any physical modification. To show feasibility of DeLightTouch, we present a set of DeLightTouch gestures as well as a proof-of-concept implementation on two off-the-shelf commercial smartwatches running Android Wear operating system.