Hearing aid technology is getting smarter all the time. It has long been possible to wirelessly transmit the sound of a cell phone, TV or music system to suitably calibrated hearing aids.
The Danish company GN ReSound is the market leader in this sector. It has been selling hearing systems that can be controlled via app like an equalizer for iPhone and Android for years now. Wireless technology in the 2.4 GHz frequency range developed jointly with Apple is used for this purpose.
Australia has even come up with the first cochlear implant that can be wirelessly coupled to iOS devices. Cochlear is the market leader in the design and manufacture of implanted hearing solutions. The new sound processor by the company Nucleus 7 transmits phone calls, music, and audio tracks from movies and games directly into the cochlea. Unlike with Android devices, iOS devices do not require a Bluetooth dongle for coupling.