The Submersible Audio Light Sensor (SALS) app works with the SALS probe, a Bluetooth Low Energy device, purchased separately from the American Printing House for the Blind. One end of the probe detects light in either air or liquids and the other end coverts detected light to sound (in the form of a tone) and sends the data to the app downloaded on an iPhone or iPad. Use of the app and probe alert a student with visual impairment or blindness that a chemical reaction has taken place (e.g., a precipitate has formed, pH has changed) in a beaker or test tube. Differences in luminance between the surfaces of objects in air (e.g., rocks or pH paper) can also be detected by the probe and app.