Guitar Tuner is the best app to tune your guitar, ukulele, banjo, and other stringed instruments. This simple and user-friendly app is based on the built-in mic of your device, so you don't need to connect to your device. It detects the string automatically and guides you through a simple and intuitive interface.

This free app has a very useful and informative interface. You can see the current string, select the desired one, and adjust the pitch.

The app has a database with over 4,000 reference tones. These tones have been recorded and arranged in a way that makes them easy to use.

The app has three modes: Auto, and Manual mode. The Auto mode detects the string automatically and tunes the string. In the Manual mode, you can select the string you want to tune.