Noteworthy Tuner is is an open-source tuner that makes it super simple to quickly and accurately tune virtually any instrument. Just open the app and play a tone, and you're already tuning.

As with all of my apps, the core feature set will always be free, and there will never be any ads.

Features:

• Chromatic instrument tuner for: guitar, ukulele (uke), violin, viola, cello, bass, and any other instrument
• Simple to use
• Detects note automatically in real-time (no need to pick the note first)
• Chromatic (not just some specific notes, but all 12 pitches in the octave)
• A4 frequency can be changed from 440 Hz to anything else.
• Both free and ad free (no ads!)
• Open source