Engineers and doctors from the University of Washington created the first app that can sound out ear infection in children with the use of a piece of paper folded into a funnel and put on a smartphone. The app works by playing birdlike chirps and the phone’s microphone will then record the sound waves bouncing off the eardrum. It analyzes the reflected sound from a healthy eardrum. If the sound received is changed, it means pus or uninfected fluid is present. Doctors who tried the app found out that the smartphone approach is as good as or can also be better than the hearing testing equipment. The university is still hoping for approval from the Food and Drugs Administration to sell the app.