Strobel

The most accurate guitar tuner on iOS. YIN pitch detection, polyphonic string detection, Strobe mode, and Intonation tool - all in one screen.

Strobel detects pitch with a custom YIN algorithm accelerated by Apple's vDSP framework - the same math used in professional studio hardware, running entirely on your iPhone with no ads, no subscription, and no internet required. TUNER • Precision needle gauge with colour-coded zones (green ±5¢, amber ±10¢, red beyond) • Live cents and Hz readout with animated digit transitions • Auto string detection — just play, Strobel locks on • Auto-advance through strings as each one reaches in tune • Haptic feedback at ±10, ±5, ±2, and ±1 cent milestones • Cents history trail showing the last 100 frames of pitch stability • Strobe Visualizer — the gold standard of precision tuning, now on iPhone • Intonation Tool — measure open string vs 12th fret, get exact saddle adjustment direction • 8 tuning profiles: Standard, Drop D, Drop C, DADGAD, Open G, 7-String, 8-String, Sweetened Acoustic • Capo support — automatic frequency shift for frets 1–7 • Reference pitch — tune anywhere from 432 to 446 Hz • Custom tunings — define your own string names and frequencies • Noise gate — adjustable threshold to filter stage noise and hum SWEETENED ACOUSTIC A tempered preset inspired by players like James Taylor — slight flat offsets per string that compensate for wound string inharmonicity, making chords sound richer together than standard equal temperament.

DESIGNED FOR IPHONE AND IPAD One screen. No tab bars. No clutter. The gauge, the note, the strings — everything visible at a glance. Dark Liquid Glass aesthetic that shifts from charcoal to emerald as you approach in tune.