Sound Tuner app for iPhone and iPad

Sound Tuner is a professional tuner app for all instruments, employing state-of-the-art pitch detection algorithm with extremely high precision (up to 0.01 cents) and sensitivity. It automatically detects the pitch, even in noisy environments. The app has several advanced customization options.

The Pro Version (available as In-App Purchase) can listen to multiple partials at once (as in strobe tuners), which allows for extremely fine tuning, particularly in the bass.

Main Features:
* compatible with many instruments (such as guitars, violin family, piano, harpsichord, etc.)
* high responsiveness and speed
* automatic sensitivity and noise cancellation
* accuracy up to +/- 0.01 Hz and +/- 0.01 cents
* logarithmic, high-precision tuning indicator
* you can choose any reference frequency and note (default: A4, 440 Hz)
* you can tune to a reference sound (for example, another instrument)
* automatic and manual note switching
* tuning any partial (up to sixth partial)
* tuning multiple partials at once (Pro Version only)
* temperament presets
* instrument presets
* battery saving mode

Usually Sound Tuner iOS app used & searched for