And this is a tuner using same algorithm: https://apps.apple.com/us/app/resonance-chromatic-tuner/id1641681952 https://apps.apple.com/us/app/resonance-chromatic

And this is a tuner using same algorithm: https://apps.apple.com/us/app/resonance-chromatic-tuner/id1641681952 https://apps.apple.com/us/app/resonance-chromatic-tuner/id16... Also very old stuff :)