Tune your musical instruments by ear with precision and ease! · Generate notes from A1 to C7 in 4 different waveforms · A4 Calibration from 415Hz to 466Hz · Sine, Square, Triangle and Sawtooth waveforms · Output volume setting · Instant load and most precise algorithm for tone emission. · Compatible with external speakers · 64-bit Universal app, works with iPhone, iPad and iPod touch!