A:Answer Hi there! No app is necessary to use the CONNECT OTC hearing aids - it can be used standalone. However, the free app offers extra customization features that may enhance your experience with the following additional settings: Band tuning, multi-level loud sound protection, directionality options, and multi-level noise reduction. When a setting is changed in the app, your hearing aids will retain that feature until you change it manually on the device, or again in the app.