Mobile Phone Control
Most modern hearing aids have an accompanying free smart phone application you can download from the Google Play Store (Android) or the App Store (Apple).
The application you download, once paired to your hearing aids enable you to access a wider variety of features in the hearing aid, so you can fine tune your listening experience. Typically this enables individual control of the left and right hearing aid volume as well as the ability to change the listening program in your hearing aid to suit the acoustic environment that you may find yourself involved with.
A number will have a tinnitus masking feature and sometimes the possibility to sculpt your own bass and treble to your own preference.