App-based tuners are mobile applications designed to help musicians tune their instruments accurately. They use the device's microphone to detect the pitch of the sound produced by the instrument and provide visual feedback, indicating whether the note is in tune or needs adjustment. These tuners are popular among guitarists, violinists, and other string instrument players. Many app-based tuners offer additional features, such as metronomes and pitch detection for various instruments. Some even include tuning options for specific styles, like guitar or ukulele. These apps are convenient and accessible, making it easier for musicians to achieve precise tuning on the go.