Stubberud A, et al. - Given the effectiveness of biofeedback in treating pediatric migraine, researchers here aimed to develop a biofeedback treatment smartphone app for adolescent migraine sufferers and to determine its usability. They conducted a prospective open-label development and usability study including 10 adolescent migraine sufferers; the participants were made to use a newly developed biofeedback app with wearable sensors that measured their muscle tension, finger temperature, and heart rate. They completed three iterative rounds of usability testing, including a 2-week home testing period. Development of a biofeedback algorithm, combining and optimizing the 3 physiological modalities, and several algorithms for sham-treatment was done. All 3 rounds of usability testing were completed by five of ten participants. Excellent correlation of the biofeedback optimization algorithm with the raw physiological measurements was observed. The intervention was safe and tolerable. This app allows the receipt of therapist-independent biofeedback for young migraine sufferers. Following a rigorous development process as well as usability and feasibility testing, this app is now ready for clinical trials.