How healthy are your lungs? Now you can test how efficient your lungs are, right from your own smartphone! An app called SpiroSmart acts like a spirometer, and even comes quite close to the accuracy of medical spirometers. All you do is take a deep breath and breathe toward your phone, which analyzes the reverberation of your lips. Have you ever used this app, or a spirometer before? I would love to hear your stories below.