Various embodiments concern sensors and other components that can be disposed beneath a variable transparency layer of a mobile device. By modifying how much voltage is applied to the variable transparency layer, a component, such as a camera, can be readily hidden when not in use. More specifically, the variable transparency layer may be substantially opaque when the camera is not in use and at least partially transparent when the camera is in use and ready to capture an image. The opacity level of the variable transparency layer can be modified by a voltage source that is electrically coupled to the variable transparency layer. The various levels of opacity could also enable the variable transparency layer to act as an electronic aperture for the camera.