GymDrops

Transform your music experience with GymDrops, the app that lets you create and save your "drops" - those precise moments in your favorite tracks that you want to replay over and over again.
Heart Rate Drop Trigger Sync GymDrops with your Apple Watch and let your body decide when the drop hits. Set a BPM threshold and GymDrops automatically triggers your next drop when your heart rate spikes. Intensity-driven music, built for real workouts.
https://www.apple.com/legal/internet-services/itunes/dev/stdeula/