1. Realize Bluetooth binding between digital hearing aids and mobile phones, perform independent fitting of hearing aids, fine-tune the hearing aid sound volume, and synchronize setting parameters to the mobile phone.2. Support users to perform repeated fittings and be able to edit, store and delete all fitting data.3. Support users’ mobile phones to control the headset to switch between different modes and scenes.4. It is convenient for users to adjust the size of hearing aids, and supports users to fine-tune low, medium and treble adjustments to better suit the users hearing sense.