This app is a really simple tuning meter (tuner). It can be used as a chromatic tuner. It supports a lot of musical instruments (8.18Hz - 12543.85Hz). When starting up this app, it begins to input the microphone sound and analyze it. Function - Tuning - Concert pitch change(400 - 490) I would be happy if you could tell me what instrument you are using. The advertisement is displayed once every 3 days.