An instrument tuner suitable to tune a variety of musical instruments, including:- Guitars (6 strings);- Basses (4 strings);- Bowed instruments (violin, viola, cello, and contrabass).- Other instruments.When you launch the app, it automatically starts listening to your environment for any sound and immediately recognizes the notes you play. So there's no need for you to preselect the note to tune.The pitch is measured very accurately, at the resolution of one cent (one hundredth of a semitone). You can see the pitch both as absolute frequency (in Hertz) and as relative frequency from the correct pitch, with the difference calculated in cents. Any difference of +/- 10 cents is acceptable to the average ear.It always uses the correct temperament system. For guitar and bass, it uses the equal temperament system, for the violin, viola, and cello it uses the perfect-pitch system, while for the contrabass is uses the perfect-fourth system. For instance, assuming A4 = 440Hz, the note G3 has a correct pitch of 196Hz on the second open string of the guitar, and a 195.6Hz, on the open G string of the violin. If you need to tune a bowed instrument to the equal temperament system, you can do that too, simply select your desired tuning system.For non string instruments (flute, clarinet, and so on) you will need to use the equal temperament system, which is the app's default setting.String instruments can benefit from a page that summarizes all your instrument's strings tuning in one place, so it will be easier for you to see if your instrument is correctly tuned. Switch to this page by simply tapping on the "Open strings" button at the bottom of the screen.The reference frequency of the middle A (A4), which is normally set to 440Hz, is adjustable, in the range 410Hz - 470Hz.Buy with confidence, if for any reason you don't like it, you can have a refund directly from Google Play within two hours from purchase. After two hours, I will issue a full refund to not completely satisfied users when you write at email@example.com.