Piano Tuner's Assistant

Piano Tuner's Assistant is a professional acoustic analysis utility crafted specifically for piano tuners, music students, piano technicians, and acoustic piano owners.

Key Features:

Real-Time Pitch Analysis: Utilizes microphone audio FFT processing to measure fundamental pitch frequencies from A0 (27.5 Hz) to C8 (4186 Hz).

Cents Deviation Gauge: Precision analog and digital pitch error meter displaying exact cents deviation (±50 cents) with flat/sharp direction cues.

88-Key Piano Map: Interactive 88-key keyboard view and comprehensive pitch deviation spectrum bar chart across the whole piano.

Pitch Stability History: Name, save, and compare multi-session tuning records over time to monitor piano string pitch drift and acoustic stability.

Reference Tone Generator: Built-in pure sine wave synthesizer producing standard reference pitch (A4 = 440 Hz, 442 Hz, 443 Hz, 438 Hz, 415 Hz).

100% Offline & Private: All audio processing runs locally on device with zero data collection or internet required.

以下为 App Store 商店页的官方介绍原文（英文）。