There are many types of apps for musicians. One of the most common being guitar tuners apps.

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    <h3>Decibel tuner</h3>
    <p>D ------- D# ------- E  ------- F ------- F#</p>
    <p>|_______|___ 82.4Hz ___|_______|</p>
    <img src="https://getmimo.com/r/needle.png">
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