X音准金耳朵 app for iPhone and iPad
This is a musical note detector. It listens and identifies the musical tone, figures out the corresponding note according to the pitch. That will be great value to Violin, Chinese Erhu and Singing lessons. With this App, students can judge the intonation accurately all by itself.
It is a full-fledged tuner also i.e. it can be used to turn your musical instruments.