Does Viiiiva work with HRV applications? January 26, 2022 22:24 Updated Yes, Viiiiva measures R-R intervals with 1ms accuracy and is, therefore, suitable to use with your favourite HRV apps. Related articles Viiiiva User Manual Configure Viiiiiva ANT+ Passthrough (iOS) Meet the 4iiii Customer Service Team How do I know which Viiiiva is mine when I'm in a group? Is Viiiiva waterproof?