Your Apple Watch becomes a breathing coach. Haptic pulses guide every inhale, hold, and exhale. No screen needed. 5 techniques: Box, Resonant, Paced, Triangle, Post-Exhale Triangle. Custom presets with adjustable timing. Sessions saved to Apple Health with heart rate. Start from iPhone or directly on Watch. Works standalone without your phone. No subscription. $9.99 once, yours forever. No voice guides, no account, no content library. indie dev from Denmark. "Pust" means "breathe" in Danish.