HA-Fit is an iPhone application developed by 永泉 柳, available for free in the Utilities & Tools category. This software allows users to remotely control their hearing aids with ease. With HA-Fit, users can adjust various settings and features of their hearing aids, enhancing their overall listening experience.

The Intelligent Control application enables users to adjust the volume, switch between different hearing aid programs, modify MPO size, fine-tune gain across frequency bands, toggle feedback and noise reduction, conduct listening tests, and monitor battery power and connection status. HA-Fit provides a comprehensive solution for managing and optimizing the performance of hearing aids through a user-friendly interface.