WiDig
This video shows the use of a WiDig to create custom controllers for mobile devices, in this case a laser harp. The WiDig is connected via Bluetooth Low Energy (BLE) to an iPad running GarageBand. The ReachCloseD sensor measures hand distance which value is used as a controller for pitch. When the beam of the SeeLaser-GreenWide actuator that shines on the Flash sensor is interrupted, a note is triggered.