Shruti - Musical Tuner

Shruti is a real-time pitch tuner built from the ground up for Indian classical music. Whether you are a Carnatic vocalist, a Hindustani sitarist, a violinist checking intonation, or a student learning to hold Sa, Shruti tells you exactly where you are — instantly. WHAT MAKES SHRUTI DIFFERENT Most tuners are built for Western chromatic scales. Shruti speaks the language of Indian classical music. It maps every detected pitch to one of the twelve swaras — S, R1, R2, G2, G3, M1, M2, P, D1, D2, N2, N3 — relative to your chosen tonic. The note name displayed is always a swara, never a generic C# or Eb. Whether you follow the Carnatic or Hindustani tradition, the swara system is universal — and so is Shruti. YOUR TONIC, YOUR WAY Set your tonic to any standard note, or hum your own Sa and let Shruti capture it. Tonic is stored as a raw frequency — not rounded to the nearest semitone — so the app works perfectly even if your shruti box, tanpura, harmonium, or drone is slightly off standard pitch. Once set, every swara is measured relative to that exact frequency. Changing tonic is as fast as a single swipe: drag left or right on the tonic button to cycle through notes instantly. PRECISION YOU CAN SEE The analog dial shows you the signed cents deviation from the nearest swara with a color-coded arc: · Green — within ±10¢ (in tune) · Yellow — within ±25¢ (close) · Red — beyond ±25¢ (needs work) Prefer a different view? Switch to the horizontal bar meter or the strobe display in Settings. HOW IT WORKS Shruti listens through your iPhone's microphone using a time-domain YIN pitch detector — no FFT, no black box. The algorithm runs on a dedicated audio thread with hysteresis smoothing to prevent the display from flickering at semitone boundaries. The result is a reading that is fast, stable, and accurate to within a fraction of a cent. PRIVACY Shruti uses the microphone only for real-time pitch detection. No audio is ever recorded, stored, or transmitted. DESIGNED FOR PRACTICE · Large swara display — readable across a room · Color-coded zones consistent across all three meter styles · Swipe the tonic button to change notes without breaking your flow · Works with the built-in mic or any connected audio interface · Recovers automatically from Bluetooth route changes and interruptions