Helix Tuner

Helix Tuner is a completely new way to tune your instrument. Unlike all other tuning apps, it does not detect your pitch at all. Instead, it combines the sound coming into the microphone with the desired tuning pitch to create a beautiful interference pattern on the screen. The interaction between your sound and the reference pitch creates an optical illusion of motion when your note is sharp or flat, and it appears stable when you're in tune.
If you are tired of digital tuners that jump around erratically, have slow or delayed response to changes in your tuning, or in general just don't give you good tuning information, then Helix Tuner is the one you are looking for.
When you manually select the tuning note, as opposed to letting the app detect it automatically, Helix Tuner is extremely resistant to background noise and higher string harmonics that confuse other tuners, causing them to jump around to higher notes and give wrong tuning information. Because the visualization system naturally responds more clearly to sounds near the selected tuning pitch, it is useful even when other musicians are playing nearby.