HotPaw Production’s Talking Tuner is an accessible tuning app designed to speak outloud feedback after a note is played. The feedback includes the name of the note, whether it is sharp, flat, or in tune, by how many cents the note is off pitch (a cent being 1 one hundredth of a semitone, or the difference in pitch between two adjacent notes), and the pitch of the note in Hertz. For the convenience of the user, when the app is set to speak notes automatically, only the note and by how much it is off pitch is spoken, though you can still swipe up to the top of the screen to see the full details.
The app worked well for what it was, though, as someone used to tuning by ear, the process went much more slowly when relying on the app than when I tune by ear. Still, this app is a definite must for any one who relies on VoiceOver and is unable to tune by ear. Furthermore, it worked when inputting sound via an interface, so it would be an excellent tool to have on hand at a gig where one might want to tune quietly before going on stage for a sound check, thereby saving the audience from listening to an instrument being tuned after it has been plugged in. The developer states that the app works best for notes two octaves below or above middle C, and this appears to be accurate. I had no trouble tuning notes within that range, but ran into issues when trying to tune a five-string bass, where even the E string failed to register. However, I was able to get a decently tuned instrument when using the harmonics at the 12th fret of each string.
To read more about or purchase the app, visit the Talking Tuner iTunes page.