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Get Erhu Tuner old version APK for Android
Fast and Easy. Erhu Tuner & Metronome
This app uses your phone's microphone to listen and analyze the sound in real time and recognize which string you are playing, indicate if your string is too low or too high.
You can also press the buttons of a string on the app to switch to manual mode, and then you can only tune the string you pressed. If you get this string in tune, then press next button and tune the next string.