Tone-Sense is a minimalist pitch-matching mini-game. Hunt a target frequency by producing any sound the microphone can pick up — your voice, a whistle, a hum, tapping or scraping an object, an instrument, or even audio played from another device. The app uses the microphone purely for on-device pitch analysis — nothing is recorded, saved, or sent anywhere. ■ How to play 1. Pick a target pitch (100 / 200 / 1000 Hz, or a custom value in 100 Hz steps up to 10000 Hz) 2. Hold the mic button and produce a sound close to the target (up to 3 seconds) 3. Release the button — the dominant frequency of your sound is estimated and compared to the target ■ Judgment tiers - INSANE — within ±3% (near-perfect pitch) - Great — within ±10% - Otherwise ■ Features - Voice, whistle, humming, tapping or scraping objects, instruments, or any external tone source — anything that produces a clear pitch works - On-device pitch detection using AVAudioEngine + FFT (Accelerate framework). No server, no disk save, no leakage - Two visual themes: Cyber (neon green) and Soft (warm cream) - Bilingual UI (Japanese / English) - In-app help sheet explaining what "frequency / Hz" means - Works fully offline ■ Privacy Data collected: none. Microphone audio is processed only in memory during a measurement, then immediately discarded. No advertising, no analytics, no third-party SDKs. "Tone-Sense" is the third entry in the Sense series (Tilt Hit / Hertz Sense / Tone-Sense).
