EverHeard
Live captions and environmental sound alerts for people who are Deaf or hard of hearing, on iPhone, iPad and Mac, with alerts on Apple Watch. Speech is captioned in the language it is spoken, in eight languages, with up to four active at once. Doorbells, knocks, alarms and your own name arrive as distinct vibrations, and urgent sounds flash the screen.
It runs entirely on your device: no account, no cloud service listening in, and it works offline after a one-time download.